Where Is Canna Hiding Their Calcium?(the Truth Behind Canna Nutrients)

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FarmerX

66
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Hello fellow cultivators,

Something has been bothering me recently, where is the calcium in Canna's Coco line?

Every major article and research paper I've studied has emphasized a minimum of 1.5:1 and a common maximum of 3:1 or 4:1 ratio of Calcium : Phosphorous.

Based on Canna's 'Guaranteed Minimim Analysis' and feed chart for "Soft Water" and "Light Feed" applications:

Veg:
105N-61P-68K-31Ca-24Mg

Flower:
165N-81P-111K-50Ca-33Mg

Bulk:
195N-171P-290K-58.5Ca-Mg

Cannas A+B label information input into canna-stats and hydrobuddy at 1ML of each per Gallon:

15N-5P-7K-4.5Ca-3Mg

That's without additives, which all provide addition phosphorous and potassium-no calcium.

Needless to say I was perplexed and tickled by this for a while. Then I found this:

Where is canna hiding their calciumthe truth behind canna nutrients

Using RO Water, this cultivator mixed 8ML of Each A and B with 1 Gallon of water and had the solution analyzed.

The Elemental NPK of analysis:

115N-40P-56K-98Ca-33Mg-18S

All values divided by 8:

14N-5P-7K-12.25Ca-4Mg-2.5S

The claimed ratio:
15N-5P-7K-4.5Ca-3Mg-?S
Actual ratio:
14N-5P-7K-12.25Ca-4Mg-2.5S

---------------

I have come to the conclusion that nutrient calculators such as canna-stats and hydrobuddy should not be used to decipher commercial nutrient recipes, they can be used as a guideline for understanding what may be present, but should never be considered accurate and should never be used as a way of adjusting inputs and values.

If you want accurate information about your feed program. There are labs and universities that will happily perform a full analysis for $50-$200, then you will have appropriate information that can be used to adjust inputs.

Be careful mixing brands and products!

Cheers,

X








 
F

FarmerX

66
33
Canna stumped me again.

I adjusted the ratios and then applied everything at bulking feed dose.

180N-180P-510K-150Ca-50Mg-25S

I've read in other forums that Canna creates their solutions for tap water. Supposedly assuming Calcium, Magnesium and trace minerals may be supplimented by source water. I don't know if I believe this though, the common theory is that most calcium and magnesium in tap water is in carbonate form, and unavailable in hydroponic solutions. Canna is a company with enough capital and resources to do the research, they would know about carbonate presence and calcium availability in harder waters-probably better than most of us.

Canna only recommends to use the bulking formula(added pK) for 7-10 days. If you were to remove the pK, the numbers read:

180N-100P-139K-150Ca-50

Returning to a 1.5:1 or greater Ca : P ratio.

I have a theory, which is a two parter:
1. Perhaps a single week of imbalance in the Ca : P ratio is not enough to create significant stress on the plant.
2. The Coco Coir medium is buffered with Ca, Mg, and K ions and is able to compensate for the incoming imbalance of nutrients.

The high phosphorous content in general is also noteworthy!
Most crops are content with a 25-35 Phosphorius PPM, increasing to 40-50 PPM during rooting and fruit set stages. Phosphorous is used to discourage stretching. Does Canna and other companies using high phosphorous values believe that we should treat Calyx development on fruit sites as if they were fruit sites on a branch?

That returns me to the original question bough, why isn't Canna increasing the presence of calcium while increasing phosphorous so much?

I'm going to email Canna today and see what's up. I've been researching different companies, and this one is messing with my brain.

X
 
Quantrill

Quantrill

235
93
the ionic calcium, magnesium, ect. reported on a water test is most certainly plant available.

"I have come to the conclusion that nutrient calculators such as canna-stats and hydrobuddy should not be used to decipher commercial nutrient recipes, "

garbage in = garbage out

if the data you put in is incorrect, of course the data output is going to be incorrect.

I have come to the conclusion that guaranteed minimum analysis from "hydro store" nutrient concentrates should not be trusted to calculate nutrient profiles.
 
F

FarmerX

66
33
@Quantrill -

Thank you very much for stopping by and contributing to the thread.

It's my understanding that calcium carbonate is ionic, are you implying that's it is available to plants for immediate uptake in a hydroponic application? I would love to hear more about this.

Perhaps I should have been more specific, you can't use those applications to calculate a commercial products NPKCaMg with information retracted from the labels as Guaranteed Minimim Analysis. It is truly garbage in, garbage out.

Again, thank you for taking he time to post here.

Cheers,

X
 
Quantrill

Quantrill

235
93
here is my water analysis
Shop water


The calcium reported is the calcium in solution, calcium ions (Ca++). It is plant available.

when a water test results list calcium carbonate, it is most likely referring to the alkalinity. A common unit used to quantify alkalinity is calcium carbonate equivalent, this is not a reference to the actual calcium carbonate content of the water, but rather just a comparison of the waters acid neutralizing power to the acid neutralizing power of calcium carbonate.

http://edis.ifas.ufl.edu/pdffiles/ss/ss54000.pdf
 
F

FarmerX

66
33
@Quantrill -

I see what you are saying now! The water analysis I have been referring to calcium and magnesium ions as hardiness.
IMG 0158


How are you managing such high alkalinity? Do you filter?

Thanks again for your input and generosity of information!

X
 
F

FarmerX

66
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General update; I did reach out to Canna, but have not heard back yet.

My AVG hardiness, tested weekly runs about 27, in a 2:1 Ca:MG assumption, that gives me 18 Ca and 9 Mg.

- Canna's bulking formula with my tap water reads as:

180N-180P-510K-168Ca-59Mg

This still falls short of the standard 1.5Ca:1P ratio.

- Canna's bulking formula with Quantrills taper water:

181N-180P-513K-210Ca-62Mg

This would be considered better, near a 1.16Ca:1P ratio. It quickly drops in the case that phosphoric acid is used as a pH Down though- Canna recommends Nitric Acid.

Hmmm,

X
 
C

costa

315
93
Hello lads . Hope u don't mind me butting in . Sounds like u know your stuff and values , hence me asking if you could have a look at this for me . I got a funny feeling I'm far out with my mix. Ro = 30 ppm . 10 L mix . 25 ml A + B , 25 ml Zym , 20 ml Rhiz and 20 ml boost . So far , so good . Now is the tricky bit , lol ,,,,, on top of this , i add 30 ppm Epsom and 90 ppm Canna Mono Cal . All this comes out at approx. 600 ppm . I'm in Canna Coco Pro Plus w/ 30 % perlite . Plants are nice and green , but a bit slow . Am I giving them too much cal ? Sorry for butting in .
 
F

FarmerX

66
33
@costa -

You are referring to PPM read by TDS, or Elemental PPM calculated based on mg/L?

I don't necessarily see anything wrong with your mix, especially if you are happy with the way your plants look and perform.

If you feel like tinkering, these are the suggestions I will make knowing that they've worked in my garden in the past using the Canna products:

- You may consider pulling back on the rhizotonic, Canna doesn't suggest more than 1.8ML per Gallon beyond the first week or two. Some growers completely remove Rhizotonic from their feed, others foliar feed it only, and even some whom macro dose at 4ml per gallon. No significant difference in my opinion, except when totally removed from the feed, there was slightly reduced growth rate-the foliar feed combined with irrigation application seemed to be most affective, but by a small margin. If you're pH is rising a lot, you can cut this out of your program, but it can also be used to increase pH if you need to. This is the biggest pH up offender, and may contain very minimal nutrients; 1K/1ML/1Gal), the emphasis being on vitamins D and a Plant growth hormone associated with root development, so a removal from the program all together once at week 4 of flower, or even veg, does not affect the end quality of flower noticeably. May be worth keeping if you run an environment that may be root stressful, where the plant has high root turn over. Part B will be your largest pH down offender, but you can't remove or reduce this without equivalent application of Part A.
- Remove 'Boost' until flower, and even then this is arguably best applied as a foliar in the week leading up to fruit set. This is an expensive product loaded with a plant growth hormone, vitamins, carbohydrates, and some phosphorous and Potassium. Unless you are not concerned with price at all, I suggest 1-2ML per gallon of 'Boost', and if you want the extra P+K that's provided by the dose of Boost' sub it out for a light dose of 'PK 13/14'. Canna recommends 6-12ML per gallon of boost. The minimim analysis suggests this rate would add 6P-12K, up to 12P-24K. The minimum analysis of PK 13/14 suggests 1ML per gallon would provide 14P-29K. Arguably phosphorous is overused in Canna nutrients, but I am not a professional with the same credentials and knowledge as the team who made the formulas. I have run 1-2ML of Boost and .5-.66ML of PK per gallon during flower without I'll affect. Beware of PK 13/14, it's a very concentrated solution that will burn your plants and blow up EC if not applied correctly, but in that same sense she's one of the most concentrated P-K boosts available at the price.
-You may be adding an excess of calcium and magnesium(less likely IMO; Canna runs a near perfect 3:1 ratio of Ca:Mg) but if plants appear content with the application, you probably aren't hurting anything but your wallet. If you have more than one plant, I'd suggest removing one or both additions of Epsom and Calcium from one of your plants feeding schedule, monitor for improved or decreased vigor or signs of deficiency.

Cheers,

X
 
F

FarmerX

66
33
Update:

I presented the Elemental PPM calculated by Canna's label and also the actual Elemental PPM calculated by the water analysis above, to Canna via e-mail yesterday. I requested their reasoning and thoughts on the Ca : P ratio, and also their reasoning and thoughts on phosphorous exceeding 50 PPM(mg/L) in nutrient the solutions.

Here's their response:

"Hello,

Well, I am not so sure of what you are asking so will say the following things and maybe it will help some.
1) Values given on the label are expressed as Mass/ mass, meaning mg solute/ kg solvent. While this can convert to ppm, no sensor used picks up 100% of what is there, and this is especially true where the ions tested are done with a method other than GC/MS., and is given
2) Phosphate listed on the label (and Potassium) use an archaic system of reporting in the amount of P2O5, Phosphorous pentoxide, which only has 40% P so the true value to expect is 40% of what the label advises. The same with K at 80% of the value as it is given as K2O. It is not our choice, just the way the world has been doing it for a few hundred years.
3) We do not work with ppm but millimoles, and the percents given are actual percent of the ion to the solution based on weight to weight.
4) There is extra Calcium and Magnesium over normal feeds as we also have to supply what the medium will take before the plant sees, so what the plant sees is less than what you test.
5) We never allow what is in the water to influence what is designed for the plant. This is a common internet mistake. Only in the medium do we place our trust and only with mediums we design. Water hardness that you refer correctly to as unavailable is a pH and pH stability issue and will affect the availability of Calcium to the plant grown in Coco especially which is why we prefer that the water is not RO water unless there are high level toxins involved. The best solution is to RO the add back tap water until the hardness stabilizes at around 120 ppm for the ppm guys here is the states, r about 0.2 mS/cm for the EC guys.
6) Using a single nutrient for both Veg and Flores means that the medium accumulates P until it fills (just about 4 weeks into a grow) then the plant sees it all as a floral nutrient. There is no overload of Phosphate when used correctly.
7) Finally, additional P is provided as needed with the addition of PK 13/14 on the correct schedule for the plant needs and only for a small window where the nutrient does not supply enough.

Hope all this helps in some way for your understanding.
Cheers
XXXXX X.(removed for privacy reasons)

--------------------------------------------------------
CANNA Research North America
It is not possible to reply to this email directly, please use the contact form on the website if you have more questions."


-----------/-------------

What I've learned:

Although very functional, the Canna line doesn't show any consistency in adhering to a specific ratio other than on it's base nutrients, respectively N : Ca : Mg : SR , noted to be constant at 10.8 : 9 : 3 : 1 and maxing out in solution at 180:150:50:17 PPM(w/o tap water consideration).

Sulfur is applied at a different ratio during flower, I notice Potassium Sulfate in the 'PK 13/14', unfortunately there is also Monopotassium Phosphate and no indication of derivative quantity or ratio. Sulfur presence may still be calculated by manually calculating the P : K ratio of Monopotassium Phosphate, then adjusting the ratio to match the 14 : 29 with Potassium sulfate, once the quantity of Potassium Sulfate necessary to reach the ratio is identified, we can then calculate the Sulfate content of Potassium Sulfate and apply it to the 14 : 29 : ? ratio. Once this is achieved, we will then understand the sulfur quantity and ratio in canna's nutrients(assuming that the 0-10-11 provided by the label is the actual guaranteed analysis and not the minimum-as we've discovered canna to hide calcium in Part A and B).
I'll be performing an analysis of plain water and another of PK 13/14 mixed with the same source water to quantify the true PPM provided.

5. Canna is not formulating their nutrients for tap water nutrient abailability, but instead for the pH buffering ability of the tap water.

6. "Using a single nutrient for both Veg and Flores means that the medium accumulates P until it fills (just about 4 weeks into a grow) then the plant sees it all as a floral nutrient. There is no overload of Phosphate when used correctly."

Is he/she implying that, at the recommend dose rates, for the first 4 weeks of a vegetative (or bloom!?) cycle the medium is consuming all the phosphorous, and only after that does phosphorous become available for plant uptake? They must mean that a portion of each feeding is being used by the medium. while an amount is still available or becoming available to the plant.

What of the jump from 100-180P PPM so late into the flowering cycle?

---------------/--------------

More thoughts/theories:

1. Canna has a theory or evidence that cannabis consumes or requires a higher level of phosphorous than most other hydroponic crops.

2. Canna is compensating for what the medium is making immediately unavailable at each feeding.
If this is true, could we theorize further that the target Elemental PPM of phosphorous for hydroponically fruiting cannabis is 50, thus any feeding amount above this is meant to buffer the Coco Coir medium instead of being available for uptake?

For example:
Full strength without the P-K boost they suggest feeding 100PPM phosphorous. If theory 2 applies, the medium is actually retaining 50 of the total P ions, leaving 5oP PPM available for plants. This theory doesn't explain the need for a spike from 100 to 180 mid fruit though, unless the cultivar or medium suddenly requires 130 PPM of Phosphorous.

3. I had previously theorized that the high phosphorous nutrient lines were created by people with theories or evidence that phosphorous causes tighter
Calyx/Bract forming as it commonly causes tighter node, fruit, and branch formation.
One way to test this theory is to administer one plant a high phosphorous feed, and a second one an identical formula with a standard/adequate phosphorous feed, and a third with very low phosphorous feed. All plants would be required to be the same cultivar and have similar environment, but could be studied for fruit density, and also fruit length versus width.

4. Canna runs a relatively low amount of Potassium in their base nutrients, and even all the way through flower with additives until the PK 13/14 is introduced. Perhaps the only reason canna is introducing so much Potassium during the peek is because one of the derivitaves is Potassium Sulfate, the plant may benefit from an increase in Potassium but the real push may be for the Sulfate content that is undisclosed at this time.

5. This may seem far fetched, but perhaps Canna could be fed at 27.77—% strength during bulking phase. This would peak at 50N-50P-142K-42Ca-14Mg, arguably a strong formula. I've actually ran near 40N-50P-60K(EC 0.6) up until 14 days from harvest in a very intense environment with impressive results, I did have to compensate for some Mg and Ca deficiencies, but I don't recall the dosage rate anymore.

--------/-------

I sent canna a respectable list of questions again, I'm sure I'll see a response in the next day or two.

To test one of my theories, I also reached out to Canna under the ploy that I was a farmer using unusually high amounts phosphoric acid to compensate for high alkalinity and pH. I then asked if it would be safe to introduce Potassium Sulfate in place of their 'PK 13/14' product and other supplements. With this question came a request for a recommended lower limit and target range for adequate Phosphorous and Potassium fertilization-assuming I could not use the canna additives. I'm hoping they give me a realistic set of parameters, as 180P-510K is pretty ludicrous.

As I'm trying to decipher their nutrients and reasoning, I keep reminding myself that people have great results running just the base nutrients, Part A and B. The only noticeable and significant change in the formula when adding their additives is Phosphorous, Potassium, Sulfur, PGR and carbohydrates.

It's amazing how this plant performs under such variety of circumstances.
 
C

costa

315
93
Wow , thanks for all that . My tap is 800 + ,,,, criminal , isn't it ? So I have to use ro . @ 30 ppm , I need to add some cal. and mag. Apparently Canna A+B haven't got enough cal. and mag. before you hit 700 ppm . Tonite I'll try and cut the ro with tap @ 200 ppm and leave the epsom and mono cal .out . Should I give them a gentle watering , or w/run off ? I don't think the roots have developed much since transplant , hence the size of them @ 5 weeks . ( 8-10 ' )
 
P

Pimples

772
143
Canna stumped me again.

I adjusted the ratios and then applied everything at bulking feed dose.

180N-180P-510K-150Ca-50Mg-25S

I've read in other forums that Canna creates their solutions for tap water. Supposedly assuming Calcium, Magnesium and trace minerals may be supplimented by source water. I don't know if I believe this though, the common theory is that most calcium and magnesium in tap water is in carbonate form, and unavailable in hydroponic solutions. Canna is a company with enough capital and resources to do the research, they would know about carbonate presence and calcium availability in harder waters-probably better than most of us.

Canna only recommends to use the bulking formula(added pK) for 7-10 days. If you were to remove the pK, the numbers read:

180N-100P-139K-150Ca-50

Returning to a 1.5:1 or greater Ca : P ratio.

I have a theory, which is a two parter:
1. Perhaps a single week of imbalance in the Ca : P ratio is not enough to create significant stress on the plant.
2. The Coco Coir medium is buffered with Ca, Mg, and K ions and is able to compensate for the incoming imbalance of nutrients.

The high phosphorous content in general is also noteworthy!
Most crops are content with a 25-35 Phosphorius PPM, increasing to 40-50 PPM during rooting and fruit set stages. Phosphorous is used to discourage stretching. Does Canna and other companies using high phosphorous values believe that we should treat Calyx development on fruit sites as if they were fruit sites on a branch?

That returns me to the original question bough, why isn't Canna increasing the presence of calcium while increasing phosphorous so much?

I'm going to email Canna today and see what's up. I've been researching different companies, and this one is messing with my brain.

X
I too have wondered about calcium and magnesium carbonate in my tap and just how available it really is....not much. but according to Canna if (i talked to them about this) thier nutrient is geared towards a fairly decent tap at 0.2 to 0.4 ec. And most base nutrients have buffers. (Nitrates) in them to make the carbonates in tap a little more available to the plant. Its still not perfect because they are still carbonates but if they arent too high (100 to 200 ppm) and you add almost any decent bottles nute line...the plant can take them up a little bit better. My tap is 110 ppm (0.2 ec) and i actually add a very tiny bit of Cali magic to bring it up to 150 -170 ppm. Then add Canna coco nute at 10 ml per part to a gallon .Its almost always perfect for all my gear.And if you read on the back of a Canna coco brick label...it says that the stuff is buffered to 0.6 ec. I would imagine mostly calcium amd mag nitrates and ph adjusters and what not. Canna is a good brand. If you dont get into all their additives...the base is pretty inexpensive. And ive used the addys...they dont do much versus without them. That Rhizotonic is some pretty nice stuff though. About like Atami Bcuzz root stimulator. And Bcuzz is almost half the cost and you only use 3/4 of a tsp per gallon. Anyways...good post.
 
P

Pimples

772
143
@costa -

You are referring to PPM read by TDS, or Elemental PPM calculated based on mg/L?

I don't necessarily see anything wrong with your mix, especially if you are happy with the way your plants look and perform.

If you feel like tinkering, these are the suggestions I will make knowing that they've worked in my garden in the past using the Canna products:

- You may consider pulling back on the rhizotonic, Canna doesn't suggest more than 1.8ML per Gallon beyond the first week or two. Some growers completely remove Rhizotonic from their feed, others foliar feed it only, and even some whom macro dose at 4ml per gallon. No significant difference in my opinion, except when totally removed from the feed, there was slightly reduced growth rate-the foliar feed combined with irrigation application seemed to be most affective, but by a small margin. If you're pH is rising a lot, you can cut this out of your program, but it can also be used to increase pH if you need to. This is the biggest pH up offender, and may contain very minimal nutrients; 1K/1ML/1Gal), the emphasis being on vitamins D and a Plant growth hormone associated with root development, so a removal from the program all together once at week 4 of flower, or even veg, does not affect the end quality of flower noticeably. May be worth keeping if you run an environment that may be root stressful, where the plant has high root turn over. Part B will be your largest pH down offender, but you can't remove or reduce this without equivalent application of Part A.
- Remove 'Boost' until flower, and even then this is arguably best applied as a foliar in the week leading up to fruit set. This is an expensive product loaded with a plant growth hormone, vitamins, carbohydrates, and some phosphorous and Potassium. Unless you are not concerned with price at all, I suggest 1-2ML per gallon of 'Boost', and if you want the extra P+K that's provided by the dose of Boost' sub it out for a light dose of 'PK 13/14'. Canna recommends 6-12ML per gallon of boost. The minimim analysis suggests this rate would add 6P-12K, up to 12P-24K. The minimum analysis of PK 13/14 suggests 1ML per gallon would provide 14P-29K. Arguably phosphorous is overused in Canna nutrients, but I am not a professional with the same credentials and knowledge as the team who made the formulas. I have run 1-2ML of Boost and .5-.66ML of PK per gallon during flower without I'll affect. Beware of PK 13/14, it's a very concentrated solution that will burn your plants and blow up EC if not applied correctly, but in that same sense she's one of the most concentrated P-K boosts available at the price.
-You may be adding an excess of calcium and magnesium(less likely IMO; Canna runs a near perfect 3:1 ratio of Ca:Mg) but if plants appear content with the application, you probably aren't hurting anything but your wallet. If you have more than one plant, I'd suggest removing one or both additions of Epsom and Calcium from one of your plants feeding schedule, monitor for improved or decreased vigor or signs of deficiency.

Cheers,

X
I remember WAY back in the day (late eighties) i ordered a small hydroponic system and clone kit from Hydrofarm when they still went by Applied Hydroponics. Anyways...the clone kit came with a generic concentrated rooting hormone solution that you diluted with a quart of water and used for a cut stem dip and swirl. That stuff was really good i thought back then (basically high auxin root promoter). I remeber when i bought my first bottle.of Rhizotonic decades later (ouch - shits expensive). Soon as i took the seal off and smelled it....exact same smell as the old Hydrofarm stuff. I suspect the ingrediants are damn near the same and Hfarm put it in a clone kit. They also had a powdered/granular grow amd bloom nutrient that came in little plastic tubs. The grow was green and the bloom was a blue powder. It had everything in it. That stuff was nice. Suoer cheap (they sold it separately also) and worked a charm. This was back when the industry was super small and growers were few and far between. Kinda off topic but it just reminded me of how much more amd expensive things have gotten. Rhizotonic is great but not 60 + dollars a liter great.
 
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F

FarmerX

66
33
Hey guys!

Another update on my conversation with Canna!

"Hello,

Thanks for all the questions and I would love to wax philosophic with you on the ins and outs of Phosphate feeding and ratios and such, unfortunately I do not have that kind of time so let me answer your direct questions. To begin, remember we are referencing coco an organic medium composed of most of the elements found in the sea, as that is where it lives and how it can fool the osmotic gradient to allow its use of sea water as a water source, and what it brings to the table as it ages has to be allowed for.
1. The koko peat fraction accumulates Phosphate, does not saturate but stays with the particles through various physical forces. Coco degrades faster than peat and as it does it leaves little charges on the remaining particle which attract strongly divalent elements like Calcium. These are mistakenly but kind of correctly referred to as the CEC of coco. These divalent ions never come off once attached, but they show up in the Ca: P : K: everything else ratios. When the next ion releases, it takes the Ca ion with it and another bare set of charges appear. Initially there are lots and lots of charges until the product is buffered, Canna Coco that is, and then the ratio of Ca, Mg, and other ions are much higher than what is needed, and all affect the ratio you refer to.
2. We recommend you use Nitric during Vegetative growth not Phosphoric. Using it during flowering will add some more, not so much but yes it does and you can compensate for it by decreasing PK usage which you will have to check by trial and error. Do not mistake Phosphate need with ratio numbers, especially not in ppm. Adding 10 – 20 ppm is not a lot compared to a system that will use considerably more. Ratios are what the plants need and what keeps the ions available in the medium at a single point in time, not across 1-3 days between watering. You certainly would want a higher Ca to P ratio during vegetative growth. Again, during the approximate 4 weeks of P accumulation the ratio, including what is added as a buffer initially, is quite high enough. You will not get enough Phosphate for function by using Phosphoric acid only. We highly suggest you refrain from using any Sulphur as coco has an abundance, especially one that is already entering into an environment where K ions are released in super abundance (which leaves the charged spots I mentioned before) and it is one of the elements we have to allow for in engineering the package. Again, it depends on what you are growing but a plant grown for the flowers and fruits, in general, require added P during that stage. We do not take the grower out of the equation and the grower must work with their own understanding of the system and adjust as they feel warrantied.
3. Depends entirely on what you are growing as to the needed or preferred Ca : P ratio.
4. No we do not make such claims that are based heavier on cultivation conditions and genetics. We do say that the proper timing of the higher P rate is required along a Phosphate utilization curve existing in plants. By keeping the Phosphate out of the solution until the timing on that curve reaches a level required beyond what the base nutrient provides, at which time additional is given for a space of 7-10 days only, which occurs at the moment the cells themselves are expanding in the fruiting structures, which effectively increases harvested yields.
5. Phosphate is critical in most energy utilizing processes as well as serving component need, which is why the higher use comes during flowering, when the plant is using more energy, burning Carbs, to make more of the Phosphate based energy components, then flowering uses more from setting up to also provide needed energy components and P containing compounds for a seed should one develop.
6. The medium is handled during initial buffering beyond the immediate need and replacing those ions washed out through attrition is the only replacement needed, along a well-studied decomposition curve based on our complete knowledge of the product and its history. If you apply water only to the coco, you will wash out these reserve ions which will upset the balance and you will see what you keep hinting at with our ratio issue, even though this system has worked flawlessly since the mid 1980’s.
7. I do not understand why it would need to compensate for these ions or whatever. Phosphate is not high. Remember, it is already in the medium in abundance, if you use our coco. If not than you are probably correct and it will take several weeks of continuous applications of the correct fertilizer to get it correct. I hope this helps some. This is about all I can say on the subject.

Cheers
XXXXX X. (Edited for privacy)

-------------------------------------------------------- CANNA Research North America It is not possible to reply to this email directly, please use the contact form on the website if you have more questions."


Alright...

I did a lot of research and reading between my original post and now. One of the things that jumped out to me was the "phosphorous utilization curve." Here's a link to an interesting article which discusses phosphorous and application timing relative to crops life cycle:
IMG 0203

(Source: http://link.springer.com/article/10.1007/BF01928506)

That's something to think about! Perhaps similar research lead Canna to believe that a heavy spike in phosphorous(and possibly other elements-through synergism and antagonism) during a specific time in the plants life created a similar performance to one that was constantly fed the same element.

I still don't understand why we would need such a high phosphorous value in the nutrients, unless it has to do with increasing magnesium uptake in a solution that some argue is lacking magnesium:
IMG 0214


I'm beginning to feel like I'll never know why Canna boosts phosphorous so much when most crops require 1/2 to 1/4 of the PPM being applied to in many popular cannabis nutrient lines.

----------------------

I am not the first to try and understand Canna's nutrients, if you are finding this thread 4-5 years from now(as I did the following), you should also read these threads by some of our favorite people.

Lucas discusses the Canna formulas and cation exchange capacity: https://www.icmag.com/ic/showthread.php?t=21119

Carl Sagan & Canna:
https://www.thcfarmer.com/community...-nutes-to-use-w-canna-coco.48644/#post-853040

Some guy tries to replicate the Canna recipe: https://www.uk420.com/boards/index.php?showtopic=237053

Unfortunately, none of these fine intellectuals had proper analysis performed on the nutrients. In my original post I presented a nutrient analysis, here is another as reference and confirmation of the Canna NPK profile:


IMG 0282


That's a 500 ml batch of Canna A+B applied at ~16ML/Gal. The nutrient solution was mixed with tap water, the irrigation suitability analysis on the tap water should be here any day to be review in reference.

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As our Canna Rep mentioned above, we must be mindful of the medium we are using, as each may have unique characteristics that must be accounted for when engineering a solution. Here is a must read post by one of our fellow THCFarmers about Coco coir medium properties and nutrients:

Hope this helps the link issue



the link didn't work. so i copy & pasted a cached version to allow it to be viewed.

Analysis of a Coco Coir Sample

All figures refer to ppm (mg/L)



S (Sulphate)
1978

P (Phosphorous)
126

K (Potassium)
3700

Na (Sodium)
2022

Ca (Calcium)
119

Mg (Magnesium)
104

Cu (Copper)


Zn (Zinc)
3.2

Mn (Manganese)
3.8

Fe (Iron)
12.2

B (Boron)
7

Cl (chloride)
3498



Take a close look at the elemental analysis of our coco substrate product. I would point out that this was a compressed product from Holland (originally deriving from Sri Lanka) which was tested after questions were raised as to why the product was seemingly killing plants.

You will note extreme levels of sodium and chloride or sodium chloride (NaCl or common salt). That is 2022ppm of sodium and 3498ppm of chloride. That is 2022mg (20.22grams) of sodium and 3498mg (34.98grams) of chloride Given that even 200 -300ppm of NaCl is dangerously high to many plants, the sodium chloride levels in this product were extreme and it resulted in disaster.

So another important factor that needs to be addressed - untreated coco coir can contain high levels of sodium chloride (salt). Try to remember that coconut palms grow well in areas of high salinity. This means they uptake a lot of salt from their environment. Plants that are salt tolerant are able to uptake salt and then displace it into areas of the plant where it does the least harm. Seemingly, much of the salt is displaced into the coir of the coconut palm (the very thing we use as a hydroponic medium). Factors that will influence the NaCl levels in any coir product include the treatment it has received prior to sale and how far inland the coconut palms are grown (the further inland the less salinity/salt in the soil/sand and hence the less salt that is uptaken by the coconut palm).

Other than this you will note 3700ppm of Potassium and 1978ppm of sulphate. This tells us that there are high levels of potassium and sulphate that are naturally present in coir products.

Due to these factors, in Integral Hydroponics, I recommended that, ideally, growers should purchase buffered coir products and use coco coir nutrients when growing in coco substrate.

OK – so the buffered products tend to cost more. Those cheap compressed blocks that you can buy from gardening centres etc are just as good as premium grade buffered coco coir – or at least that’s what’s asserted by some.

Some of the cheaper compressed products may perform well with a good flushing prior to use (hopefully, if very high levels of NaCl are present you may be able to flush it out with water before the salt detrimentally affects plant health) but the fact is, that buffered and hydrated products in almost all cases are superior to unbuffered products and there are very good (scientific) reasons for this.

Coir needs to be buffered to offset the NaCl levels, to compensate for natural potassium and sulphate levels and to charge (prepare) the medium with the right ions to facilitate adequate cation exchange capacity (CEC) within the medium.

Signs of toxicity (high levels of NaCl in coir substrate)

Slow/stunted growth
Unhealthy plants
Yellowing
Burning
Rusting on edges of leaves
Rust spots on leaves


Flushing and Buffering compressed coir blocks

Let’s now talk about how to use (prep) a cheap compressed or uncompressed (non buffered) product that you buy through garden centres. That is, how to buffer the compressed product correctly, in the same way that some coir substrate producers/on sellers do (e.g. CANNA, Atami B’cuzz etc).

It’s important to note that some coir products available through garden centres etc may be sold as soils/potting mixes with NPK added – avoid the use of these products; they aren’t developed for hydroponics. Besides this, the compressed blocks are cheaper and you’re now about to learn how to turn these into high quality buffered hydroponic coir substrates.

Here’s our buffer formula used to pre-treat and hydrate compressed coir blocks.



Coco Substrate Buffer

(Used for preparing non-buffered coco substrates such as compressed coco blocks)

Calcium Nitrate 290 g/l
Magnesium Nitrate 280 g/l
Magnesium Sulphate 10 g/l
Ferric EDTA 2 g/l

Make 1L by beginning with 500ml of RO (demineralised) water. Add ingredients one at a time, dissolving each ingredient before adding the next. When all ingredients have been added, top up to 1000ml (1L) with RO water.

What I recommend you do is hydrate the coir blocks in mains (tap) water. That is, fill a bucket or tub with mains water. Measure the EC of the mains water before adding the compressed coir block/s. Let’s say it’s EC 1.0 for arguments sake. Add the compressed coir block and allow it to expand. Stir the water and coco substrate around and then measure the EC again. You’ll no doubt find the EC is now much higher. OK, now run mains water through the coir (you may find a bucket with holes and mesh at the base helps here). Run the mains water through (flush) the coir until the water that has passed through the coir (runoff) is no more than EC 1.0 - 1.2. I.e. Original mains water EC ideally matches that of the runoff.

Now fill up a bucket with demineralised (RO) water and dilute the buffer concentrate to 1.4 EC (700ppm). Place the hydrated/expanded and water flushed coir into the diluted buffer solution and leave to soak for at least one hour.

After one hour or more, take out the now buffered coir and squeeze out the excess fluids so the coco substrate is not saturated/water logged. You may find drying it in the sun for a while helps. .

Ready to go – you now have a high quality buffered coir product at a fraction of the cost that you would pay for similar products through stores. I’d also recommend that you mix the coir with perlite. 60% coir to 40% perlite when using it as a run –to-waste medium.

Tip: Many of the compressed coco blocks that are purchased through gardening centres are (when uncompressed) coco powder. If this is the case, look for varying grades of coco substrate, working from fine to larger fibres and mix them into a single product to increase air porosity within the media. The ideal coir particle size is 0.5 – 4mm.


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Optimum Coir Particle Size for Optimum Yields

Research has demonstrated that optimum growth rates will be achieved in “medium particle sized” (0.5 – 4mm) coco substrate. The research, conducted on tomato plants and seedlings, measured germination and growth rates in coarse particle (greater than 4mm), medium particle (0.5 – 4mm), fine particles (less than 0.5mm), and raw coco peat (unseived material) with findings that the highest numbers of leaves and growth rates were achieved in medium particle sized coir substrate.

Quote: “Tomato plants grown in coco peat with medium sized particles, showed significantly higher plant heights when compared to tomato plants grown in coco peat with other particle sizes.” 1

1. Effect of Particle Size of Coco Peat for Greenhouse Tomatoes: H.K.M.S
Kumarasinghe. Department of Crop Science, Faculty of Agriculture, University of Rahuna


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Mixing Coir and other Media

Perlite

Each particle of perlite consists of tiny air cells that provide for a large surface area. Because of the shape of perlite, large air gaps form between the particles. This means there is plenty of oxygen available to the root system.

Perlite doesn’t compact and because of this maintains an ideal balance of oxygen and water (oxygen moisture ratio).

Perlite is very tolerant to overwatering which makes it very forgiving medium. Because of its nature, perlite allows excess water to drain off and provides an air ratio of approximately 40- 45%.

Perlite, like coco, has thermal insulation qualities, which provides the root zone with a high degree of security against heat.

Perlite is a very cost effective medium. It is about half the price of expanded clay.

Lab Analysis: Comparison of Perlite and Coco Samples

Perlite

Air Porosity: 40%
CEC: 5.0
Water Holding: 28.9

Coco (6mm particle size)

Air Porosity: 20%
CEC: approx 63.1
Water Holding: 66.5

Buffered Coco (Medium Particle Size Sample)
Particle Sizes:

MATERIAL > 2mm % 7.5
MATERIAL 1.00 - 2.00 mm % 25
MATERIAL 0.85 - 1.00 mm % 27.5
MATERIAL 0.30 - 0.85 mm % 15
MATERIAL 0.075 - 0.30 mm % 22.5
MATERIAL < 0.075mm % 2.5

CATION EXCHANGE CAPACITY 56.69
Water Holding: 51
Air Porosity: 30%

Re Air porosity measurements

There are two methods that are commonly used for measuring Air Filled Porosity (AFP) in the coir. These are:

The European EN-method: Loose coir (no compression) is saturated with water and allowed free drainage for 24hrs. AFP is then measured. A quality buffered product such as Atami coir measures at approximately 35 – 40% AFP under this method.

The Dutch BLGG method: Coir is slightly compressed in a container and saturated with water where it is then allowed free drainage for 24hrs. Atami buffered coir measures at 20 – 25% AFP under this method.

Author’s note: Optimum AFP = 30%. Realistically, even the highest quality coco coir may become saturated and compressed over a 10 or so week growing cycle (represented AFP being the Dutch BLGG method at 20 – 25%). For this reason, I recommend mixing perlite with coir at a 60 - 70 (% coco substrate - 30 -40 (% perlite). This ensures optimum AFP at 30% throughout the crop cycle. I.e. Perlite has approximately 40- 45% AFP and will increase AFP in the coir.



Clay Balls/Expanded Clay (e.g. Hydroton) and Coco Substrate

I’ve noticed on internet forums that many growers speak of using expanded clay instead of perlite when working with coco substrate and RTW growing.

Other than this, many growers seemingly use expanded clay at the base of the pots to allow for “better drainage” (not a bad idea). That is, they line the base of their pots with expanded clay to perhaps two to three inches and then fill the pots with a mixture of coco substrate and expanded clay.

I personally can’t see a problem with using expanded clay with coco substrate other than perlite has a higher air capacity than expanded clay (45% versus approx 30 - 35%). Other than this expanded clay offers the roots less security than perlite and is an effective conductor of heat.


Coco Nutrition

We have seen that coco substrate contains naturally high levels of potassium (K) and therefore a nutrient formulated for coir will have lower potassium (K) levels than a standard nutrient. Other than this we have also seen that coir naturally contains sulphates and therefore a nutrient developed for coir would contain less S than a standard nutrient (or so this should be the case – at least one “hydro” manufacturer has been known to pass off standard nutrients labelled as coco formulations).

Some years ago I had one European company’s formulas for coco and standard bloom analysed. The company makes a single product for coco (one formula used for both grow and bloom) and therefore it is a one size fits all product. Largely however, it is formulated as a bloom product. This was likely due to Dutch growing methodologies where the growth cycle tends to be very short before the light hours are switched down to 12/12 to induce flowerset (i.e. multiples of small plants per square metre). Other than this, you can see our buffer formula (a reverse engineered copy of this company’s formula) contains high degrees of calcium nitrate and magnesium nitrate, meaning a high degree of NO3 Nitrogen and Ca and Mg is present in the coco medium to help facilitate growth in the early veg stages (the extra Ca, N and Mg will be quickly depleted by vigourously growing plants and it is recommended that you use a coco grow formulation if vegging for an extended period of time).

OK – so let’s now have a look at the two analyses (a side by side comparison of this company's bloom standard against their coco –bloom- formulation) and check what the differences are.

SAMPLE
Prod X
Prod X
Prod X
Prod X

NAME
FLOWER A
FLOWER B
COCO A
COCO B

SERIAL #
051167
051168
051147
051148

ELEMENT





NH4N (mg/L)
128.3
2158
117
1184

NO3N (mg/L)
43080
10642
42200
6780







S (mg/L)
45.55
11740
47.1
7930

P (mg/L)
15.96
17280
14.4
16190

K (mg/L)
37830
26070
6880
16780

Na (mg/L)
55.2
136.1
39.8
122.3

Ca (mg/L)
32840
586
53600
620

Mg (mg/L)
225.7
10180
7470
12310

Cu (mg/L)
1.32
11.24
1.2
9.4

Zn (mg/L)
0.51
59.6
1
69.2

Mn (mg/L)
0.59
121.4
3.2
122.9

Fe (mg/L)
190.6
4.19
199.5
2.1

B (mg/L)
< 0.5
60.9
0.9
63.4

Cl (mg/L)
12.5
32.85
13.4
34.3

pH
2.92
2.97
2.8
3.04

COND. (dS/m)
141.5
92.7
103.4
82









Look closely at the numbers. You will find they are quite different and that the theory (what I have been saying) matches the formulation. It is clear to see that the coco formula contains far less potassium (K) than the company’s standard bloom formula, less sulphate, more calcium, more magnesium and so on. That is, the formulas differ vastly. One is formulated for an inert medium (standard bloom) and one is formulated for a hydroponic medium that contains high levels of potassium and sulphates (i.e. coco substrate).

Potassium competes with magnesium and calcium and therefore both magnesium and calcium levels have been raised in this formulation to compensate for natural potassium levels within the media. Other than this, due to the cation exchange properties of coir, some calcium is immobilized (held) and higher levels of Ca are required in formulation (along with Ca Mg buffering prior to use).


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Understanding Cation Exchange Capacity (CEC) and Coir


CEC relates to a soils/substrates ability to attract, retain, and exchange cation elements.

Cation elements are elements with positive electrical charges; these being potassium (K+), ammonium (NH4+), magnesium ( Mg++), calcium (Ca++), zinc (Zn+), manganese (Mn++), iron (Fe++), copper (Cu+) and hydrogen (H+). While hydrogen isn’t a nutrient it affects the degree of acidity (pH) of a substrate and, for this reason, is important.

Some nutrients have negative electrical charges. These are called anions and include nitrate (NO3 N), phosphate, sulfate, borate, and molybdate.

The word "ion" (as in cat –ion and an – ion) simply means a charged particle; a positive charge is attracted to a negative charge and vice-versa. This means both positive and negative charged nutrients/elements form a symbiotic relationship and are available for uptake.

High CEC values indicate that a soil or substrate has a greater capacity to hold cations and where there is high CEC there is a large nutrient reserve.

Coco substrate has high CEC.


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Actually, let me further assert the point now that soil and coco are very different mediums and need to be handled very differently where nutrition is concerned (among other things). Here is an analysis of the same company’s soil flower formula – this analysis was conducted in 2003 in Australia (it may differ from the European formulation but I suspect not). This is a single part formula, whereas our coco formula is a two part A and B set.

Element
Flower
Nitrate N (g/L)
22.0

Ammonium N (g/L)
5.0

Urea N (g/L)
6.1

Phosphate P (g/L)
9.6

Potassium (g/L)
35.3

Calcium (ppm)
137

Magnesium (g/L)
5.94

Iron (ppm)
115

Copper (ppm)
13

Manganese (ppm)
123

Zinc (ppm)
62

Sulphate S (g/L)
6.86

Sodium (ppm)
456

Chloride (ppm)
815

EC (mS cm-1)
105.0

pH
1.74






It’s worth pointing out that this analysis is in grams per litre, so to achieve mg/L you simply need to understand that 1000mg (or 1000ppm) equals 1 gram. Therefore 22.0grams Nitrate in the flower formula equals 22,000mg Nitrate. Other than this, elements found in lower concentrations are listed in ppm. 1 ppm equals 1mg/L.

This is a fairly simple fertiliser blend which is about 22% solids. EC is high and pH is low because it is made with nitric acid. Relative to other major nutrients, calcium is quite low. As such it is not suited to fertigation (i.e. intermittent drip feed as in run-to-waste systems), but is suitable for less frequent, heavy applications (as you would typically apply in soils).

Now compare the soil bloom numbers to the coco formulation – you’ll note that they are extremely different.

You will also note the product contains urea. Urea, CO(NH2)2, doesn’t supply any ammonium nitrogen (NH4 Nitrogen) or nitrate nitrogen (NO3 Nitrogen) and is completely different form of nitrogen to both NH4 N and NO3 N . Urea is widely used in soil applications but is seldomly found in hydroponic formulations.

You will note that the soil flower formula contains 35.3 grams of potassium (or elemental K) which equates to 35,300mg/L of potassium (elemental K). Now compare this to our coco formula and note that it contains 23660mg/L when we add the potassium mg/L in part A and B. Now compare the sulphate levels in the two formulas. In the soil formula there is 68,600mg/L of elemental S, whereas in the coco formula we have 7977 mg/L of S. Now, compare the calcium levels in each formula. In the coco we have 54220mg/L while in the soil formula we 137mg/L.

Compare all the numbers if you like and you will find massive differences between a nutrient that has been formulated for soil against one that has been formulated for coco. I hope this clarifies my point that coco and soil are extremely different mediums and require very different treatments. Coco is coco and soil is soil - let's not get them confused.

We’ll talk about how to make these soil formulas later in the book when we discuss the various approaches to optimising yields in soils. There are many ways to skin this cat and we’ll discuss this subject in depth and provide you with several formulations (some of which are manufacturer direct).

Ok, so here’s how to make our own coco nutrient based on the European formulation. It is a product I’ve worked with many times and a product I’ve always considered a good coco nutrient, hence providing the formula in the book. …… (Section deleted for the website)



pH measurements in Coir

Coco coir buffers pH in the range of 5.5 – 7. However bacterial activity and nutrient quality can have an impact on pH stability within the media.

Another misconception I have commonly encountered is that by measuring the run off (waste) in coir it is possible to measure the pH of the medium. Let’s quickly dispel with this myth. Coir media will retain some elements and release others (a process of preferential retention of cations) based on the uptake needs of plants and the prevailing conditions of/within the media.

Because of this, measuring the run off (waste) will not reflect the pH within the coir medium (i.e. the rhizosphere environment of the plants).

The correct way to measure pH, in coco substrate, is to take samples of the media from around the root zone. These samples are then added to distilled water at a 5:1 ratio (5 parts distilled water to 1 part media), then vigorously shaken or blended and tested with a pH meter. This method will provide you with the correct pH within the coir media (rhizosphere) environment.

Feed Regime

In Integral Hydroponics Edition 1 to 4, I recommended multiples of smaller feeds allowing for between 10 – 30 per cent run off. Technically, at least from a agricultural (science) perspective this is the recommended way of feeding.

If using RO (demineralised) water I would recommend a 20% run off (waste) regime.

If using mains (tap) water, I would recommend run off (waste) be maintained at 30 percent due to naturally present salts that are often found in tap water supplies. Elements such iron (Fe), magnesium (Mg), calcium (Ca) and sodium (Na) and chloride (Cl) which combined form common salt (NaCl). Sodium and Chloride normally occur together and are not taken up to any degree by most plants, especially sodium; therefore, they tend to accumulate if present in significant amounts.

In some cases tap water supplies can contain high EC/ppm levels of these salts (ions) and this can detrimentally affect the growing medium. Therefore, in order to circumvent any problems that can occur as a result of this, I recommend a higher waste percentage if using mains water than if you were growing with RO or rain water.

I should also add some information now, regarding feed regimes in coco substrate.

Since writing Integral Hydroponics (originally published in 2002) I have seen growers using all manner of feeding techniques and achieving extremely good results. One friend - a long time and very advanced grower - who had been using a wide channelled NFT system switched to coco coir and contrary to my advice began hand watering. I was somewhat perplexed by why he would go this way but I’ve always preached KISS (Keep It Simple Stupid) and was intrigued by his methods. For the next 10 or so weeks I watched closely as my friend Feral saturated his pots full of coir twice daily (during the lights on period) with a resultant approx 50 per cent run off on each feed.

“Mate, you’re over watering” I contended,” the medium is too saturated and you’re reducing the natural air porosity of the medium. (A quality coco substrate product will possess approximately 30 per cent air porosity, which is ideal for rhizosphere health).

“Yeah, but they look great and they’re growing faster than anything I’ve ever grown before”, he responded. To this I couldn’t argue; indeed, the plants were as healthy as any I’d seen and were growing at a rapid rate.

On his first grow he realised a 30 - 35 per cent increase in yield to what he had been achieving through his much touted (bells and whistles) wide channel NFT system. Of course, at this point he was sold and began switching all of his friends to coir substrate RTW growing (after years of promoting the wide channelled NFT system via internet forums to all who would listen).

The moral of the story is this. There are ideals where agricultural (scientific) principles are concerned. However, what I have learned (gained) from Feral and others is that coco substrate tends to be so forgiving, that whether you feed multiples of small feeds with 10 – 30 per cent waste (methodology correct) or whether the medium is hand watered and therefore more saturated, you will achieve great results.

Coco Substrate and Sciaradae (Fungus Gnat, Shore Fly)


Because coco substrate is organic it slowly decomposes in its wet state. This causes the release of nitrates as part of the decomposition process. There’s not much wrong with this as long as the nitrate release is minimal (which it is). However, this nitrate release is what attracts Sciaradae (fungus gnat). Sciaradae are commonly found in organic composting material. Therefore, coco substrate can be a highly effective attractive media for Sciaradae.

Sciaradae, shore flies or fungus gnats are often present in conjunction with pythium. Fungus gnats feed on rotting vegetation and other decomposing organic material. It is not certain whether fungus gnats are drawn to crops that are suffering pythium because of the presence of decomposing organic material or whether fungus gnat is responsible for introducing the pythium. It is more likely that the fungus gnats are attracted to rotting vegetation that is inhabited by pythium fungi (oospores). The gnat larvae (1-2mm white maggots with black heads) can live on a diet of pythium oospores before some of them mature into the flying stage (adults) and carry fungi to other crops. This means the presence of the fungus gnat could be a precursor to a pythium outbreak in your crop.

Other than this, Sciaradae larvae are laid by the adults in the growing medium and their food source largely consists of the roots of the plants and decomposing material.

Adult Sciaradae resemble tiny fruit flies. When they are put under a magnifier their wings can be seen to have, what look like, accentuated veins. Sciaridae have a life cycle of egg, larvae, puparium, and adult. While the adult flies will only live a few days, one female fly can lay as many as 200 eggs. The lifecycle from egg to adult can be estimated at 3-4 weeks. For this reason infestations occur at a rapid rate.

Sciaridae eggs are laid around the soil/media surface. These hatch into glossy, legless larvae with black heads. The larvae are equipped with a sharp pair of mandibles, which are used for sawing and rasping into the soft stems and roots of the plants.

Controlling Sciaradae

Pesticides: I have found that after using numerous approaches and products (biological and pesticide) the Permethrin based products (Coopex, Axe etc) are the most effective treatment for totally eradicating Sciaradae from the crop. Permethrin is non systemic and and degradates (neutralises) quickly which makes it ideal as it is not up taken by the plant in any way.

The product I typically work with is Coopex WP 250g/kg powder which comes in 25gram sachets. Coopex is manufactured by Bayer and is widely available in most countries. Mix one sachet to 10 litres, hand water (drench) the media and leave for an hour. After this, flush with pH adjusted nutrient and you are ready to go.

Yellow sticky traps hung at media height will trap the adult Sciaradae. This will help reduce numbers. More importantly it will allow you to monitor whether Sciaridae are present in the growing environment.

Tip (About Sciaradae)

Look out for:

Signs of the pest through the use of yellow sticky traps

Deformed leaves and generally unwell plants can indicate an infestation of Sciaradae

Recycling the Media

Coco substrate can be used in more than one crop cycle if it is prepared correctly prior to reuse.

The key here is in cleaning the media of dead root material (cellulose) and priming it with a buffer before reuse.

I have noticed on forums that many people speak of using Zyme (e.g. Cannazyme, Sensizyme) products for breaking down the dead root material. This is an area of concern due to the fact that while fungal cellulose enzymes are definitely effective at breaking down cellulose (after all, this is what they do in nature) the products sold through the hydro industry possibly/probably are inert. I.e. Devoid of enzymes.

There are serious question marks over the shelf life of liquid enzyme products. That’s not to say that enzymes are a bad thing -without a doubt they have a place in hydroponics/agriculture and can be potentially beneficial to plant health. However, as with friendly bacteria, the sale of these products through the “hydro” industry is, often, greatly over simplified (talked up and hyped). That is, the enzymes are contained in a liquid state and because of this they may or may not be present/active when they are purchased off the shelf. Other than this, enzymes aren’t so dissimilar to bacteria in that they need a complimentary environment in which to remain stable and work. However, by their very nature enzymes are unstable and herein lies the problem. I.e. If I make a liquid concentrate and then put it on a shelf for months at a time will there be enzymes present or not when that product is purchased? Probably not....

One producer who sells a Zyme product claims they have tested their competitors Zyme formulas and found that they were (to quote) “junk”. They go onto say, “Enzymes have a shelf life. They can expire in their bottles.” Other than this they claim to have purchased five different companies formulas (from several locations), including their own, and after testing their competitors’ products they were found to be “inert, meaning there was no biological activity left in them.” Of course, their formula, when tested, came through with flying colours.

Back to reality and the science – let’s avoid the scam factor that is too often proliferated by a few to so many.

So, what is a reliable/effective means of recycling the media?

Trichoderma Harzianum (T.harzianum)

A lot of research has been done with a mould called Trichoderma harzianum with very positive findings. Trichoderma harzianum is a friendly mould that colonises the rhizosphere and competes with other organisms.

Trichoderma is parasitic to other moulds such as pythium, fusarium and phytopthora. That is, Trichoderma protects the plants from these organisms, all of which are capable of destroying your crop.

Trichoderma enhances plant growth due to its ability to produce beneficial enzyme complexes. Trichoderma can also survive for long periods in a host, and needs only minimal carbon levels to ensure its subsistence. Trichoderma also stimulates root growth while breaking down cellulose (dead root matter etc) and therefore is an extremely effective and reliable way to treat media for reuse.

Coco substrate, more so than any other hydroponic medium, provides an ideal environment for friendly moulds and friendly bacteria.

To recycle the media effectively, remove as much dead root matter as you can by first cleaning, washing and sieving the media and then apply a treatment of T.harzianum to the coco substrate. Maintain its use for several weeks (better yet – throughout the entire crop cycle) and watch your plants grow.

Which brings us to our next point – the use of ‘friendlies’ in coco substrate.

Understanding Friendly Bacteria

This is an area which is largely misunderstood by many indoor growers so I thought I’d expand on the science of friendly bacteria in hydroponics.

Friendly bacteria protect the plant from water born pathogens such as pythium and fusarium. Other than this, they help in nutrient uptake and produce plant growth promoting substances. They can also protect plant surfaces from attacks by pathogenic microbes through direct competitive effects and production of anti pathogenic compounds.

For these reasons, the use of friendly bacteria in hydroponic growing systems has advantages over sterilisation (i.e. the use of monochloramine or hydrogen peroxide etc).

The Science of Friendly Bacteria

In nature non-harmful or beneficial organisms naturally combat harmful pathogens such as pythium and fusarium. Generally speaking non-harmful bacteria numbers explode at a faster rate than harmful bio organisms. As the non harmful bacteria numbers explode they form biomass around the rhizosphere of the plant. This biomass prevents harmful organisms entering the rhizosphere of the plant.

In addition to this, some bacteria are beneficial to plant growth. These bacteria are commonly known as plant growth stimulating bacteria (PGSB).

In nature, friendly bacteria (or friendly moulds) are naturally found in environments that are able to support them (bio-diverse environments). A bio-diverse environment ensures that the microorganisms survive and thrive. On the other hand, if the environment is lacking and is not able to support them, the bacteria will die out very quickly.

For instance, at least one “hydro” company promotes the use of mycorrhizae fungi in hydroponic growing systems and sells products to this effect. However, it is important to note that mycorrhizae fungi cannot colonise and sustain biomass in high phosphorous (P) environments (i.e. hydroponic systems) and therefore their use and viability/effectiveness in hydroponic settings is questionable. That is, the mycorrhizae fungi cannot colonise and sustain biomass in a hydroponic growing system unless the nutrient has been formulated with low phosphorous levels to cater for colonisation of the fungi (this is not advisable because the nutrient would then be lacking in phosphorous).

Mycorrhizae fungi are suitable for low phosphorous environments and are ideal for soil amendments where regular P fertilization isn’t taking place.

Here are some these useful links/articles in regards to Coco Coir characteristics:

http://hortamericas.blogspot.com/2015/07/buffering-coir-not-necessary-if-its.html?m=1

http://blog.botanicare.com/calcium-magnesium-and-coco/

http://www.pthorticulture.com/en/tr...ion-exchange-capacity-soilless-growing-media/

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I am still digesting this information myself, and will return again shortly.

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costa

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Hi Farmer . Thanks for all the effort u put in here . Just wondering re. that chart saying 16 ml / gal . Isn't that over 4 ml / L ? With a ppm of 30 on my ro water , how much cal. and mag. would you add in veg . on top of whats already in the A+B ? My last run I tried to leave the extra cal. and mag. out for a couple of feeds , and they started to go pale on me . I just don't want to give them to much cal/mag . Have you got a chart that shows the ppm's required for a healthy plant in veg .
 
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Pimples

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Whats always got me through more times than not... living in different areas in this country (usa) with vastly different regional and local water supply is this...if you cant get a report on EXACTLY whats in the water...just make it 0.2 to 0.4 EC whether you have to take some EC out with a reverse osmosis filter (too hard) and add back until you hit 0.2 - 0.4 target or add up (too soft) with a simple calmag product. Just about any of them will do. Then add your base nutrient and pH adjust according to substrate medium and cultivar. You should be good to go.
 
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