Advice on E.C and watering frequency in coco/perlite

  • Thread starter Flowerpower420
  • Start date
  • Tagged users None
F

Flowerpower420

95
33
Hi guys i am a little confused with EC'S and watering frequency,

I currently have 4 plants in 11l pots using 70/30 coco and perlite pre buffered bags.

Im also using the full mills nutrients range and im having a big headache with keeping EC'S in range and keeping the meduim wet/aerated

I cannot possibly follow the mills recommended feeding chart as the second i start to ramp up the strength of feeding the plants show signs of tip burn and nitrogen toxicity. The highest i can possibly go is 1.4EC MAX (At this stage of flower mills recommends upto 2.5 E.C i flow peak flower), but my outflow keeps slowly creeping up to the high 1.9-2.0+ with only baby food of 1.4E.C.....with another ballache of rootzone PH slowly dropping into the mid to high end of 4.5-5. Preventing optimum rootzone PH levels for phosphorus and potassium uptake. (I PH my solution to 6.0-6.2).

Now i have tried so many different things to counter this such as, lighter nutes more frequently as im currently doing now so im giving them 1.4 E.C, 0.5l every 3 hours to keep the medium constantly Saturated between 90-100% to try and combat salt build up but sure enough within a couple of days the run off is sky high,

Ive also tried allowing it to dry out for 24 hrs and flushing with calmag and ph tap water to push out exess salts and nutrient build up but the same thing happens when feeding resumes,

Ive tried lowering calmag and increasing base nutes, lowering base nutes and increasing calmag, eliminating calmag altogether which just leads to deficiencies within a couple of days, im at a total crossroad here...

Im getting more stable results with the 4 smaller but frequent feedings during lights on but tbh it just isnt practical Nor cost effective as im tipping 80% of what i feed down the toilet, But because im keeping the moisture content so high its also messing with my humidity percentage and is going to cause mould issues as im in mid-late flower now.

When i feed, my run off is way way way more than it should be, i seem to put more town the toilet than the plants are drinking just to try to keep E.C'S within range

Has anyone got any experience with mills nutrients using coco? If so what was your regime to keep a nice balance between feeds, moisture levels and salt build up.

Im flushing weekly before the next week feed schedule so the substrate is fresh and can uptake that next given weeks nutes without adverse effects but like i stated....its getting a bit too impractical.

Im thinking about autopots for my next grow but with eratic E.C's im a little unsure if this is a good idea as with auto pots there is NO run off which "in my head" will make things ALOT worse with no way of pushing salts and excess nutes out the pot. Sorry for the rambling on guys im just trying to put asmuch info in as i can.

Cheers in advance

Peace out ✌️
 
Last edited:
phxazcraig

phxazcraig

542
93
I've just finished growing 4 plants in 3.5 gallon Airpots in Coco Coir. (Roots Organics, 70/30 coco/pearlite). I did a drain to waste system built according to cannabisforcoco.com.

All was well in veg. Actually grew too fast in a way. During veg, my inputs always exceeded my output EC. I'd put in 1.2 and get out 0.8. Or less. And that without tip burn for the most part.

I was doing 4x daily fertigations, with low EC gradually rising from about 0.3 to 1.5 or so.

And then I flipped to 12/12 for flowering and everything changed. I still don't have an answer, just some more data points.

I should mention that I didn't really test runoff the correct way, which would be to sample water from each pot during runoff. Instead, I measured in the runoff container which mixed all four of my plants together. When I did investigate more closely, I found one pot that had a lot higher runoff EC than the others (but still never found the right cure).

In flower, I ended up with EC's in the 1.0-1.5 range, but EC seemed to rise about 20-30 points with every feeding. And by now I was up to 5x daily feedings.

When I was getting runoff EC's in the 1.8 range with 1.0 going in, I tried to fix it. First, I increased watering amounts in both time and frequency. Went from 5x daily to 7x daily (every 2 hours during lights plus one in the middle of the night). Went from 20 second waterings to 30 then 45.

Went from maybe 20% runoff to probably 80%. I had bucket after bucket full of high-nute runoff. Not uncommon to have 20 gallons of it sitting around. I fertilized my house plants. Then my outdoor plants. Then my outdoor trees! I had lots of runoff, and while it rose slower, the EC's were still rising.

A couple of times I just plain flushed a lot - not a true 'flush' with low nutes, but rather just pump the rest of the reservoir out through it and refill. Perhaps 7-8 gallons to 4 plants all at once. THAT dropped my runoff to just about equal my input, and then it started rising again 0.02-0.03EC at a time. I ended up reducing my watering times (but not frequency) and just periodically 'reset' the runoff by pumping extra volume through.

Now about that runoff - mostly I used it to water other plants, and I just mixed up new nutes every 2 days or so. (4 days once I replaced my 14 gallon reservoir with a 30 gallon). But especially during those purge/flush times I would just dump a bucket or two back into the reservoir and fix the pH. (pH always dropped in runoff compared to input).

A couple of notes that might be useful to track down the culprit. I was using 6 inch halo drippers, which put out a pretty decent spread of water. But I suspect there were still some channels through the coco that streamed water while there were also dry-ish spots nearby. I did use a wetting agent (yucca powder) to try to avoid problems, but I don't know how effective it was. Probably not a bad idea to periodically rotate those halos during the grow. But it's hard to turn them once the plant gets a certain size.

A possibly huge problem I found late in the grow had to do with the amount of water pumped out of the reservoir. I have a 30 gallon reservoir that is about 30 inches high. Per cocoforcannabis.com, I put a simple centrifugal pump in the reservoir and connected it to a timer. I also added an anti-siphon feature (which works spectacularly well) to prevent the water from siphoning out to the plants. But 30 inches is a lot of height difference between full and low states! What I discovered was that my water volumes were completely different when the water was low in the res compared to when it was full. I need to measure, but the volume difference was extreme. With a full res, a 20 second watering gave me about 19 seconds of full-blast halo squirting. With low res, it looks like it took 10 seconds just to build up enough pressure in the halos for them to really start squirting, and then suddenly the time was up. I'm thinking more than a 50% drop in water volume compared to full reservoir.

I'm not sure how to fix this last issue, but it makes a lot of data collected from the grow meaningless. I simply don't know how much watering I was giving them per day. Based on runoff though, way more than 20%. (At one point about 7 gallons in for 6 gallons out, daily.)

I also saw tip burn. I went from judging nutrient amounts based on output EC more than input. After all, if I'm seeing 1.8EC in the runoff, the roots were probably seeing even higher than that, so I just started reducing my input EC until the output at least seemed in a reasonable range. My input EC ended up around 1.0 toward the end of the grow.
 
F

Flowerpower420

95
33
Wow man, seems like we are both stuck between a rock and a hard place!

Thing is im manually watering by hand so haven't got any issues with dry spots within the medium as every time i feed i "Flood them" with 2litres of feed to make sure no possible dry spots. And the feed soaks down into the medium and a level and constant rate.

Im feeding 4x daily with more than ample run off like you. Like you said, 80% of runoff is still unused. But the brand im using is not a cheap one and its costing an absolute fortune to do one run from veg to flower because of the amount i need to make up just to push through and waste.

Now i know the option ive chosen is a "Drain to waste" system but i also need to be realistic.

At the moment im pumping through 8litres of feed per pot, 4 pots daily!! = 32litres of feed daily to feed 4x 11litre pots is totally wasteful and very very expensive.

Im wondering if the coco fibres could be leaching in exessive nutrients, holding onto them and causing a toxic build up in the rootzone. As i cant honestly see it being a salt build up due to how wet the medium is and how often im pushing any salt build up out.

Every article i read and video i watch people say coco is definitely the way to go for beginners....im finding that hard to believe at the moment as its giving me more problems than enough. I just cant seem to strike a balance for a straight forward grow.

I might try coco and cork mix for my next run or maybe try a different brand of better quality coco to see if its the coco itself thats causing these eratic issues. If that still persists then looks like il be changing nutrient line then maybe a different strain of plant to see if its the genetic thats refusing to co-operate.

Ahhhh man looks like this could take a while....

Thanks for sharing your experience and results mate atleast its not just me. I thought i was doing something seriously wrong as coco seems to be a generic and basic medium to grow with, with relatively few issues. Seems like there are exceptions to every rule!
 
Shayne010944

Shayne010944

1,002
113
I’d half your nute strength and feed multiple times a day , also try straight ph waterings

Try feed , water water feed at 5 times a day I’d possible and use half strength what your nute line says.
 
F

Flowerpower420

95
33
I’d half your nute strength and feed multiple times a day , also try straight ph waterings

Try feed , water water feed at 5 times a day I’d possible and use half strength what your nute line says.
Awesome mate! I will give it a shot. When you say straight ph...do you mean NO ph adjustment from tap OR ph to 6.0? Cheers man 🤜🤛
 
Clearbluesky

Clearbluesky

297
63
Alot of people don't even check the run off, try using maxibloom at a EC 1.0 going in and in veg PH 5.8 in flowering bump it up a little if you want to 1.3 EC and PH 6.0 to 6.2 and forget about checking runoff, if plants look good don't worry about it. Run off can have you chasing things all the time. The important thing is what you are putting in and that is all you need to worry about. Keep it easy. Also master blend 3 parts works very good too. Here's a plant that was 61 days from seed a auto feed calmagic and maxibloom was it.
 
Screenshot 20220526 065049
Aqua Man

Aqua Man

26,480
638
Start at about 0.8 EC and work up to 1.6 EC as they grow.

These will help you understand media in general and coco specifically.


 
F

Flowerpower420

95
33
Start at about 0.8 EC and work up to 1.6 EC as they grow.

These will help you understand media in general and coco specifically.


Ah brilliant thank you so much! 😊
 
F

Flowerpower420

95
33
Alot of people don't even check the run off, try using maxibloom at a EC 1.0 going in and in veg PH 5.8 in flowering bump it up a little if you want to 1.3 EC and PH 6.0 to 6.2 and forget about checking runoff, if plants look good don't worry about it. Run off can have you chasing things all the time. The important thing is what you are putting in and that is all you need to worry about. Keep it easy. Also master blend 3 parts works very good too. Here's a plant that was 61 days from seed a auto feed calmagic and maxibloom was it.
WOW! nice. Yeah i think ive got no option to either cut strength of feed dramatically BUT im also scared of not "Juicing" them enough during flower so i get a horrible, Airy, low yield. Trouble is mills recommends an E.C inflow of 2.2 at this stage of flower and i know not to take what they say as gospel but if i dont feed em enough how are they going to grow into BIG flowers....suppose its a balancing act thats only going to come with time and experience.

I dont want to have my girls on a diet if i "Should" be feeding them up for size like a bodybuilder lol.
 
F

Flowerpower420

95
33
Hey guys just a quick update.....
I flushed the medium to rid of any salts or exessive nutrient build up then kept my E.C inflow at 1.2 for the past week. Its safe to say they are finally co-operating now and the highest the run off E.C is coming out is 1.4 with 3 feeds daily.

9AM - 2l
2PM - 1l
6PM - 1l

Total of 4L daily split between 3 feeds at light strength seems to be the sweet spot.

Because of all the bullsh*t out there of FEED FEED FEED i think its more than likely that most people OVERFEED their crops rather than UNDERFEED causing this exact issue, with the added pressure from most hydro shops coaxing people to over-use the nutes so you will buy more frequently. at the end of the day the plant will take in what it needs and that it. Any residual causes problems.

New feeding schedule....
Per 20L.....Tap water is 0.3 E.C,

1ML - vitalise
10ML - calmag
20ML - A
20ML - B
40ML C4
30ML ULTIMATE PK
TOTAL = 1.2 E.C


For anyone whos interested or having the same issue lowering nutrient strength and frequent lighter feedings has definitely fixed this particular issue. Thanks so much to the guys that helped me on this one. Very much appreciated.

Peace out ✌️👍
20220530 182217
20220530 182126
20220530 182121
20220530 182110
20220530 182054
20220530 182050
20220530 182039
20220530 182033
 
Aqua Man

Aqua Man

26,480
638
Hey guys just a quick update.....
I flushed the medium to rid of any salts or exessive nutrient build up then kept my E.C inflow at 1.2 for the past week. Its safe to say they are finally co-operating now and the highest the run off E.C is coming out is 1.4 with 3 feeds daily.

9AM - 2l
2PM - 1l
6PM - 1l

Total of 4L daily split between 3 feeds at light strength seems to be the sweet spot.

Because of all the bullsh*t out there of FEED FEED FEED i think its more than likely that most people OVERFEED their crops rather than UNDERFEED causing this exact issue, with the added pressure from most hydro shops coaxing people to over-use the nutes so you will buy more frequently. at the end of the day the plant will take in what it needs and that it. Any residual causes problems.

New feeding schedule....
Per 20L.....Tap water is 0.3 E.C,

1ML - vitalise
10ML - calmag
20ML - A
20ML - B
40ML C4
30ML ULTIMATE PK
TOTAL = 1.2 E.C


For anyone whos interested or having the same issue lowering nutrient strength and frequent lighter feedings has definitely fixed this particular issue. Thanks so much to the guys that helped me on this one. Very much appreciated.

Peace out ✌️👍View attachment 1249382View attachment 1249383View attachment 1249384View attachment 1249385View attachment 1249386View attachment 1249387View attachment 1249388View attachment 1249389
The feed feed feed has to do with runoff. Ppm wise i find max needed is 1.2-1.6 EC depending on the genetics and environment which is different for every grow.

Bot sure if i linked this before .

 
F

Flowerpower420

95
33
The feed feed feed has to do with runoff. Ppm wise i find max needed is 1.2-1.6 EC depending on the genetics and environment which is different for every grow.

Bot sure if i linked this before .

Ah fab! Thanks for all the help and top advice guys 👍✌️
 
Clearbluesky

Clearbluesky

297
63
I've never been to a hydro shop before, now I use master blend 3 parts and buy it at 25lbs which will last years if you grow in soil, but DTW you can still get a lot of grows from it, some people say the numbers are to high on the base, but when you mix things all up the numbers change a lot so no need to worry about the high numbers on the base. Just another option if you don't want to buy the hydro stores products.
 
Like2Grow

Like2Grow

233
63
Im thinking about autopots for my next grow but with eratic E.C's im a little unsure if this is a good idea as with auto pots there is NO run off which "in my head" will make things ALOT worse with no way of pushing salts and excess nutes out the pot. Sorry for the rambling on guys im just trying to put asmuch info in as i can.

I'm using Autopots in coco/perlite with MegaCrop nutes for veg and Kelp4less bloom pack for flower. I leave the plants in the autopots over night and have been putting them outside with no water during the day. On strong weather days they stay in with the plant just picked up and twisted to be out of the water which is easy with square pots. The main water line needs to be turned off and disconnected before the plants are lifted. The plants dry out during the day then get a drink with what I choose to feed. By early afternoon the pots are very light so they feed well. With 3 plants in the tent (4x4) it's easy to take care of. With a large grow it would be a PIA.

I'm sure the E.C.'s are erratic but the plants grow well. The first photo shows main water line disconnected at the bottom of the pic after valve was turned off. Plant turned and sitting out of water/ nutes. Second is the ladies (week 2-3 of flower) sitting out enjoying part of an overcast day. Obligatory bird poop on outside plant leave included :-) (sort of like Where's Waldo game... where's the poop?) .

DSC01516a



DSC01520a
 
F

Flowerpower420

95
33
I'm using Autopots in coco/perlite with MegaCrop nutes for veg and Kelp4less bloom pack for flower. I leave the plants in the autopots over night and have been putting them outside with no water during the day. On strong weather days they stay in with the plant just picked up and twisted to be out of the water which is easy with square pots. The main water line needs to be turned off and disconnected before the plants are lifted. The plants dry out during the day then get a drink with what I choose to feed. By early afternoon the pots are very light so they feed well. With 3 plants in the tent (4x4) it's easy to take care of. With a large grow it would be a PIA.

I'm sure the E.C.'s are erratic but the plants grow well. The first photo shows main water line disconnected at the bottom of the pic after valve was turned off. Plant turned and sitting out of water/ nutes. Second is the ladies (week 2-3 of flower) sitting out enjoying part of an overcast day. Obligatory bird poop on outside plant leave included :-) (sort of like Where's Waldo game... where's the poop?) .

View attachment 1255920


View attachment 1255937

I'm using Autopots in coco/perlite with MegaCrop nutes for veg and Kelp4less bloom pack for flower. I leave the plants in the autopots over night and have been putting them outside with no water during the day. On strong weather days they stay in with the plant just picked up and twisted to be out of the water which is easy with square pots. The main water line needs to be turned off and disconnected before the plants are lifted. The plants dry out during the day then get a drink with what I choose to feed. By early afternoon the pots are very light so they feed well. With 3 plants in the tent (4x4) it's easy to take care of. With a large grow it would be a PIA.

I'm sure the E.C.'s are erratic but the plants grow well. The first photo shows main water line disconnected at the bottom of the pic after valve was turned off. Plant turned and sitting out of water/ nutes. Second is the ladies (week 2-3 of flower) sitting out enjoying part of an overcast day. Obligatory bird poop on outside plant leave included :-) (sort of like Where's Waldo game... where's the poop?) .

View attachment 1255920


View attachment 1255937
Wow mate they look really nice!

Yeah, "Apparently" coco is the ultimate noobs medium to start with but ive had nothing but issues and headaches with one thing or another. If i ramp up feed strength i get ridiculous problems with EC and salt build up leading to toxicity and burn, on the flip side i keep EC'S low and as close to stable as i can possibly get then i end up with an under fed plants and diminished yeilds.

Thing is its going to be quite hard and extremely awkward having to move the plants out of the autopot bases as i was planning a "fixed" autopot setup with 2x scrog nets.....hmmmm maybe if im still going to have problems even with the EC's in the autopots then i may have to re-think as once the plants have been woven into the scrog nets its going to create a nightmare!

Thanks for sharing mate 👍
 
Madmax

Madmax

4,733
313
Yeah i dont like auto pots as you cant flush out the salt buildup you would get if the plants arev sucking it back up into the pot..top feed is the best way.im still quite fresh at growing indoors and im finding it very easy as my enviroment and light used run very well .its very stable..and plants loooove stable.they dont like sharp increases in feed ..i feed once a day.and i feed light strength.keeping it simple phing 5.86 to 5.95. When i increase feed i do it very slowly .i veg for 5 weeks and ppm is at 500 at begining of flower and will peak at 580ppm ..my enviroment and canna nutes used work very well at this ppm..guys might think im under feeding but my yields tell another story..
 
F

Flowerpower420

95
33
Yeah i dont like auto pots as you cant flush out the salt buildup you would get if the plants arev sucking it back up into the pot..top feed is the best way.im still quite fresh at growing indoors and im finding it very easy as my enviroment and light used run very well .its very stable..and plants loooove stable.they dont like sharp increases in feed ..i feed once a day.and i feed light strength.keeping it simple phing 5.86 to 5.95. When i increase feed i do it very slowly .i veg for 5 weeks and ppm is at 500 at begining of flower and will peak at 580ppm ..my enviroment and canna nutes used work very well at this ppm..guys might think im under feeding but my yields tell another story..
Yeah mate im with you on that one! Ive been told countless times that im severely under feeding my girls with 1.2EC being the highest i can possibly go and thats still causing build up so i still need to "Mini flush" weekly with a lil calmag and ph 6.0 to reset the meduim for the following week ahead as EC rises my medium PH becomes very acidic dropping as low as 4.5! Tbh im really not enjoying using coco i have considered soil but i have been told that yeilds do suffer compared to coco or DWC.
 
MercDod

MercDod

145
43
I grew in the coco coir and perlite mix as you did but used 5 gallon fabric pots. I watered once a day. If ec out was over 300 (.3) more than I put in, I just back off a little on next feeding. This lets the plants tell me how much it wants. I always made sure EC output was a little higher than EC input. When I got this part right the ph (which was way off started to become better as well). I tracked my ph but never did anything to try and correct it. My thought pattern ; the plant takes what it wants, leaves the rest which gives you your input ec plus the residual it did not use.
 

Latest posts

Top Bottom