Ph Dropping From 5.8 To 3.9 Overnight! What Is Causing This?

[cemchris]

The lockout might be from the PH dosing. Remember PH down is a source of P. Silica is going to require more PH down then not using it. You have to account for the added P because of this. Why I run my P so low in my mix cause I'm getting around 30ppm of P just from my PH down dose on mix. Week 4 is about the time they do a full transition from stretch/flower production to full on flower mode. P from LKB, on top of Base Duo P, then adding P every time they get dosed. If you see Mg def on lower leaves is Mg. New growth is Ca. They look the same. Most of the time a Lockout of Mg, when you have plenty, has to do with K not P or the ratio of Ca:Mg. When are you running LKB? All throughout the cycle? Have you done a water report on your base water (i forgot from the first thread we talked about this in). The big concern I would look for is Fe and Carbonate in the base water. Both of those are things that can cause problems specially off well depending on the source. Granted you might have a good dose of Ca in the base water but the problem is it might be Calcium Carbonate which you don't want in high doses. That will have a neg effect on nute mixes. Have you tried dropping LKB out of the line and running strait Duo? Does the the same thing happen at the same time?

As you said before you have tried different nute lines with no avail. Duo is just fine. It's not actual nutes (per say) just might be the strength or the ratio after everything gets added on top of base water.

What exactly are you mixing per gal on everything? Do you have an idea how much PH down is getting added throughout a 1 week dose on the rez including the initial mix of the rez (using a store bought PH down or strait acid)? Just want to break it down to take some of guess work out of it. Why a base water report is good to adjust off of and see what exactly you are feeding ppm wise of each to get an idea if you are hitting a problem area. Easier then guessing. I've only used 3 part and have done a lot of breakdown/tweaking on it not Duo. Just need to look at exactly what the ratio it is when mixed.

Edit:

Starting EC is about 0.5

Water is currently being tested. Waiting for results.

Cool will wait to see that. 0.5 EC starting water is considered hard. You will most likely have to tweak with something like that. For 3 part you would run hard water micro vs reg micro in that situation. Why I'm leaning towards carbonate buildup and interaction with the mix.

 

[Aqua Man]

The lockout might be from the PH dosing. Remember PH down is a source of P. Silica is going to require more PH down then not using it. You have to account for the added P because of this. Why I run my P so low in my mix cause I'm getting around 30ppm of P just from my PH down dose on mix. Week 4 is about the time they do a full transition from stretch/flower production to full on flower mode. P from LKB, on top of Base Duo P, then adding P every time they get dosed. If you see Mg def on lower leaves is Mg. New growth is Ca. They look the same. Most of the time a Lockout of Mg, when you have plenty, has to do with K not P or the ratio of Ca:Mg. When are you running LKB? All throughout the cycle? Have you done a water report on your base water (i forgot from the first thread we talked about this in). The big concern I would look for is Fe and Carbonate in the base water. Both of those are things that can cause problems specially off well depending on the source. Granted you might have a good dose of Ca in the base water but the problem is it might be Calcium Carbonate which you don't want in high doses. That will have a neg effect on nute mixes. Have you tried dropping LKB out of the line and running strait Duo? Does the the same thing happen at the same time?

As you said before you have tried different nute lines with no avail. Duo is just fine. It's not actual nutes (per say) just might be the strength or the ratio after everything gets added on top of base water.

What exactly are you mixing per gal on everything? Do you have an idea how much PH down is getting added throughout a 1 week dose on the rez including the initial mix of the rez (using a store bought PH down or strait acid)? Just want to break it down to take some of guess work out of it. Why a base water report is good to adjust off of and see what exactly you are feeding ppm wise of each to get an idea if you are hitting a problem area. Easier then guessing. I've only used 3 part and have done a lot of breakdown/tweaking on it not Duo. Just need to look at exactly what the ratio it is when mixed.

Edit:


Cool will wait to see that. 0.5 EC starting water is considered hard. You will most likely have to tweak with something like that. For 3 part you would run hard water micro vs reg micro in that situation. Why I'm leaning towards carbonate buildup and interaction with the mix.

What about the ph drop? Any ideas or did I miss it?

 

[cemchris]

What about the ph drop? Any ideas or did I miss it?

Need more info

 

[cemchris]

What about the ph drop? Any ideas or did I miss it?

Why I'm leaning towards carbonate buildup and interaction with the mix.

My guess at this point

 

[Dirtbag]

I mean my ph drift is always slower in flower. I can't out my finger on it yet. But like I say I think it's a combination of the plants process and rapid growth. Root respiration, nutrient uptake and concentration, calvin cycle at it's longest and growth at it fastest I think adding these all up can explain it. The part I'm missing most about is the ion and exchange since we don't have the same media as say soil or coco. @Dirtbag just started flowering a week or 2 again so hopefully tagging him will get him to look at his changes in ph drift with the same buffer.

I still feel even a small amount ratio wise of ammonium/ammonia with the increased nutrient concentrations and uptake due to growth rates makes this more pronounced in hydro. You see during flower in soil the tendency for soil ph to plummet and it always attributed to nutrient build up or dying bacteria colonies but I believe there is more to it. The difference is these plant processes and everything else I listed are slower in soil as are the growth rates so I believe it's much less pronounced. The buffering capacity of course would be key and that's where I would lean towards adjusting. Of plant health is not impacted as long as you keep the ph in order than I don't see a need to fix it other than to find out the root cause.

Just my thoughts on paper

Thanks man. I'm checking ph in the blocks as well as the leachate a couple times a day and so far it's stable as hell. EC is rising in the blocks a bit between feedings but to me that just means they're taking up a bit more water than nutes. I was told by a couple growers that's what I want to see, is leachate ec coming out 0.1-0.2 higher than it's going in. If my target is 1.5 in the block and I get 1.6 leachate I keep EC at 1.5 going in. If it comes out at 1.7-1.8 I can either increase frequency of irrigation cycles or the volume flowed per cycle, or just lower the EC of the input to say 1.2 to balance the EC in the block around 1.5.

But like I say, lately (with the exception of the dead battery in my pen mishap) I've been feeding at 1.5ec and ph 5.7-5.8 and I get leachate around 1.7ec 5.5ph and solution in the block syringe tests is 1.5 ec and 5.8ph an hour after feeding.

Low ph in the runoff could be a bunch of things, either from excessive uptake of positively charged nutrient sources, lack of uptake of certain acidifying nutrients like phosphorus from insufficient runoff or overfeeding of P causing buildup, or possibly acidifying bacteria growing in the rootzone. An outbreak of Lactobacillius or acetobacter could do it.
Has the OP been feeding added sugar sources like molasses or anything?

 

[RFT]

If plant health is not impacted as long as you keep the ph in order than I don't see a need to fix it other than to find out the root cause.

Plant health is great. No signs of deficiencies. Finished product quality is superb. BUT Im pretty dissatisfied with my cola size or lack thereof. The plants do plateau at about the 4 week mark. So I think these issues are both related symptoms of the same core issue. Whatever that core problem is, Im determined to figure it out. I've never had plants that dont get a cola before. It tells me something is wrong.

 

[Aqua Man]

Plant health is great. No signs of deficiencies. Finished product quality is superb. BUT Im pretty dissatisfied with my cola size or lack thereof. The plants do plateau at about the 4 week mark. So I think these issues are both related symptoms of the same core issue. Whatever that core problem is, Im determined to figure it out. I've never had plants that dont get a cola before. It tells me something is wrong.

High P comes to mind. I think I said it earlier and @cemchris touched on it also

 

[Aqua Man]

Using say potassium bicarbonate in a new res.since you will need to get rid of the acid and not treat the result may solve the issue and add stability. I would say it's worth a shot. Adding 1/4 to 1/2 a tsp per 5gal will give a boost to k and keep P levels down instead of pk boost or MPK. To a fresh res. Also changing to sulfuric acid in flower or permanently may also help.

 

[RFT]

The lockout might be from the PH dosing. Remember PH down is a source of P. Silica is going to require more PH down then not using it.

I originally thought this might be the problem. That the silica artificially raised the pH and then extra pH down had to be added. And after the Silica was uptook, there was an abundance of pH down left in the solution. This issue would be consistent across nutrient brands.

Similar to the theory that the P-K was also providing it's own buffering and once eaten, pH would drop. Except in the case of the P-K shortage, it would explain the small colas. The silica would not. This theory would also be consistent across nutrient brands since I was not going full strength on the other brand's P-K because at a certain point there was coagulation due to some reaction to the water so I had to scale it back. Possibly further shorting the plants of P-K

Then I focused on the algae and eliminated it to no avail.

You have to account for the added P because of this. Why I run my P so low in my mix cause I'm getting around 30ppm of P just from my PH down dose on mix. Week 4 is about the time they do a full transition from stretch/flower production to full on flower mode. P from LKB, on top of Base Duo P, then adding P every time they get dosed. If you see Mg def on lower leaves is Mg. New growth is Ca. They look the same. Most of the time a Lockout of Mg, when you have plenty, has to do with K not P or the ratio of Ca:Mg. When are you running LKB? All throughout the cycle?

Running it starting in week 2. Didnt get to heavy doses until week 7. I was pretty much running the generic GenHydro feed chart. I was under the impression the FloraDuo line was pretty spoon fed. But I didnt account for the fact that those feed charts are super generic and cant possibly account for all the different grow system types & their various degrees of efficiency. I'd like to think Im running a pretty good system with chillers & all that jazz. Maybe too efficient and I just havent accounted for how well the system was delivering P-K at certain stages. Considering I start with 5" clones, do no veg time, and they are 3' tall in about 3-4 weeks and have tons of nodes & branches. The early development of the plants is spectacular and speaks to the benefits of hydroponics. It's the final half of the grow cycle that has been less than magical.

So have accelerated the feed chart on my newest cycles. Running the "Late Bloom" mix earlier now to lower nitrogen and raise P-K levels. We'll see how this makes a difference. Maybe it will, maybe it wont. But if it doesnt, then I can check the P-K theory off the list.

Have you done a water report on your base water (i forgot from the first thread we talked about this in). The big concern I would look for is Fe and Carbonate in the base water. Both of those are things that can cause problems specially off well depending on the source. Granted you might have a good dose of Ca in the base water but the problem is it might be Calcium Carbonate which you don't want in high doses. That will have a neg effect on nute mixes. Have you tried dropping LKB out of the line and running strait Duo? Does the the same thing happen at the same time?

As you said before you have tried different nute lines with no avail. Duo is just fine. It's not actual nutes (per say) just might be the strength or the ratio after everything gets added on top of base water.

What exactly are you mixing per gal on everything? Do you have an idea how much PH down is getting added throughout a 1 week dose on the rez including the initial mix of the rez (using a store bought PH down or strait acid)? Just want to break it down to take some of guess work out of it. Why a base water report is good to adjust off of and see what exactly you are feeding ppm wise of each to get an idea if you are hitting a problem area. Easier then guessing. I've only used 3 part and have done a lot of breakdown/tweaking on it not Duo. Just need to look at exactly what the ratio it is when mixed.

General Hydro pH Down but have also used alternative brands that were citric acid based. Same issue persisted.

Duo should have the tweaking already done for us. They developed it by basically taking 3 part and the Lucas method, and then making a 2-part program with it. Granted, if following the feed chart, there is still plenty of room for me to screw up the A:B ratios & supplements. Which is my current theory.

Week 4 was as follows:

Mid Bloom
A - 5 ml/gal
B - 15 ml/gal
LKB - 2.5 ml/gal
Si - 2.5 ml/gal
Diamond Nectar - 5 ml/gal

Cool will wait to see that. 0.5 EC starting water is considered hard. You will most likely have to tweak with something like that. For 3 part you would run hard water micro vs reg micro in that situation. Why I'm leaning towards carbonate buildup and interaction with the mix.

The test results are in...

No E Coli or measurable Bacterias.

Calcium - 39 mg/L
Magnesium - 19 mg/L
Nitrate as N - <40 mg/L
Iron - <100 ug/L
Manganese - <20 ug/L
Arsenic - <2.0 ug/L

Total Hardness - 175 mg/L

The lab said this was a little on the hard side, but according to GenHydro, the "hardwater" 3-part is only necessary if Total Hardness is 200 or more. Calcium if 70 mg/L or more. FloraDuo is made to still work for semi-hard water use https://www.hydrofarm.com/f/i/2l87nsl/Flora Duo_5897.pdf and since I've lowered the A-part as of late, that might compensate for the hardness of my water source.

So yes there is Cal & Mg in the well water. And the Diamond Nectar is there to help chelate it so it is eaten. Thus why I pulled the CaliMagic from the nutrient regimen some time ago.

 

[cemchris]

I originally thought this might be the problem. That the silica artificially raised the pH and then extra pH down had to be added. And after the Silica was uptook, there was an abundance of pH down left in the solution. This issue would be consistent across nutrient brands.

Similar to the theory that the P-K was also providing it's own buffering and once eaten, pH would drop. Except in the case of the P-K shortage, it would explain the small colas. The silica would not. This theory would also be consistent across nutrient brands since I was not going full strength on the other brand's P-K because at a certain point there was coagulation due to some reaction to the water so I had to scale it back. Possibly further shorting the plants of P-K

Then I focused on the algae and eliminated it to no avail.



Running it starting in week 2. Didnt get to heavy doses until week 7. I was pretty much running the generic GenHydro feed chart. I was under the impression the FloraDuo line was pretty spoon fed. But I didnt account for the fact that those feed charts are super generic and cant possibly account for all the different grow system types & their various degrees of efficiency. I'd like to think Im running a pretty good system with chillers & all that jazz. Maybe too efficient and I just havent accounted for how well the system was delivering P-K at certain stages. Considering I start with 5" clones, do no veg time, and they are 3' tall in about 3-4 weeks and have tons of nodes & branches. The early development of the plants is spectacular and speaks to the benefits of hydroponics. It's the final half of the grow cycle that has been less than magical.

So have accelerated the feed chart on my newest cycles. Running the "Late Bloom" mix earlier now to lower nitrogen and raise P-K levels. We'll see how this makes a difference. Maybe it will, maybe it wont. But if it doesnt, then I can check the P-K theory off the list.



General Hydro pH Down but have also used alternative brands that were citric acid based. Same issue persisted.

Duo should have the tweaking already done for us. They developed it by basically taking 3 part and the Lucas method, and then making a 2-part program with it. Granted, if following the feed chart, there is still plenty of room for me to screw up the A:B ratios & supplements. Which is my current theory.

Week 4 was as follows:

Mid Bloom
A - 5 ml/gal
B - 15 ml/gal
LKB - 2.5 ml/gal
Si - 2.5 ml/gal
Diamond Nectar - 5 ml/gal



The test results are in...

No E Coli or measurable Bacterias.

Calcium - 39 mg/L
Magnesium - 19 mg/L
Nitrate as N - <40 mg/L
Iron - <100 ug/L
Manganese - <20 ug/L
Arsenic - <2.0 ug/L

Total Hardness - 175 mg/L

The lab said this was a little on the hard side, but according to GenHydro, the "hardwater" 3-part is only necessary if Total Hardness is 200 or more. Calcium if 70 mg/L or more. FloraDuo is made to still work for semi-hard water use https://www.hydrofarm.com/f/i/2l87nsl/Flora Duo_5897.pdf and since I've lowered the A-part as of late, that might compensate for the hardness of my water source.

So yes there is Cal & Mg in the well water. And the Diamond Nectar is there to help chelate it so it is eaten. Thus why I pulled the CaliMagic from the nutrient regimen some time ago.

2 thumbs up for the info and thoroughness. Let me work through the feed with the water report and see what it is. Yeah duo was a more recent addition to the line why I didn't think there would be any issue from those nutes directly, also that you stated you saw this problem across the other lines. Good to know about the duo and semi hard water. Means they run the Fe lower (issue I always had with micro from 3 part. dosing it heavy gets the Fe up there). Let me see what I can come up with and try to eliminate any of that stuff as a root of the problem.

Yeah I remember you explaining the system in the first round. I think your system is 100% spot on and don't believe that is the root of any of the problems. In fact I think the thoroughness has helped you avoid most of the common problems. Why this is stumping me a little but want to eliminate the easy stuff before diving into the harder stuff.

Edit: Real quick are you getting any preciptate out of the solution? Your dosers are direct feed into the rez if I member right correct? Not inline on the feed water?

 

[RFT]

Yeah I remember you explaining the system in the first round. I think your system is 100% spot on and don't believe that is the root of any of the problems. In fact I think the thoroughness has helped you avoid most of the common problems. Why this is stumping me a little but want to eliminate the easy stuff before diving into the harder stuff.

You and me both. I've got a ton of hydro experience. This has been incredibly frustrating considering I've never experienced issues like this in any of my other facilities.

Edit: Real quick are you getting any preciptate out of the solution? Your dosers are direct feed into the rez if I member right correct? Not inline on the feed water?

No fallout.

The dosers feed inline on a closed loop that pulls from the resi and sends it back to the resi. And does so at such a slow rate that the nutes are heavily diluted far better than could ever be done by hand unless you have the patience to sit their and add nutes via eye dropper.

I've also tested the order in which the nutes are added. Which pumps they pull from, etc. No difference. Granted, it's very important when adding nutes by hand that the order be correct (Silica first, then micro, give both time to buffer, etc). But my system inherently works around those potential pitfalls.

 

[RFT]

Welp. Week 5 in a zone. Day 3.

pH dropped overnight from 5.72 to 5.32

Gonna add fresh water to get the pH back up to around 6.0 ... this will dilute the EC some. So fresh nutes will get added.

Long story short, doesnt appear that the lower N / higher P-K ratios fixed the issue.

Plants healthy tho. Stacking nicely. Best run yet but still much room for improvement clearly.

 

[Aqua Man]

If you feel brave see post #88 I'm kinda thinking its combination like i say can put a finger on it but I would only start with 1/4 tsp per 5 gal max if ya do maybe even per 10gal just to be very conservative and possibly switch to sulfuric acid. I can't say for sure it will fix the issue but I know it will control it better. I know from experience that high P levels promote huge growth rates of certain algae species. I have a feeling the high P is the problem with your growth and the PH is just a byproduct of several different things and some i can not explain.

The potassium bicarb at 1/4 tsp per 5 gal should give you a bit under 30ppm of K and leave the P out which i feel will be beneficial to you. It will also provide a better buffering capacity. The switch to sulfuric acid will also reduce P and the sulfur will benefit terp and flavinoids.

One thing that sticks out to me is that you said even with citric acid this is happening. Critic acid breaks down extremely fast and is almost useless in hydro. So the increase in acidity is actually a result of the something with the system or plants processes. It can be caused by ammonia/ammonium, decay of organic matter like dead algae or sying roots. I can't say why but i feel high P has something to do with this. Again I can say something in the system or the processes of the plant are causing it... I just can pinpoint which and it may be a combination. I'm betting if you add no buffer and no PH down you will still see this PH drop.

 

[bunkerking]

Damn, still happening? You appear to be nice/smart dude. Hope you get this problem fixed bud.

 

[RFT]

. I'm betting if you add no buffer and no PH down you will still see this PH drop.

If I had to bet, I’d agree with this statement.

Also because I’ve done cycles with low P-K added, multiple nute brands. Same issue persisted.

EC is at 1.37 ... I cant go much lower. So that rules out EC being too high.

I’ve raised P-K, so this theory has hit the skids.

Upon closer inspection of the zone, I am noticing some N toxicity. Darker green leaves w/ some curling down. Very odd since Ive cut the nitrogen down lower than ever before.

Frustrating.

 

[RFT]

Damn, still happening? You appear to be nice/smart dude. Hope you get this problem fixed bud.

I used to think I was smart LOL.

The evidence isnt in my favor at the moment.

 

[Aqua Man]

If I had to bet, I’d agree with this statement.

Also because I’ve done cycles with low P-K added, multiple nute brands. Same issue persisted.

EC is at 1.37 ... I cant go much lower. So that rules out EC being too high.

I’ve raised P-K, so this theory has hit the skids.

Upon closer inspection of the zone, I am noticing some N toxicity. Darker green leaves w/ some curling down. Very odd since Ive cut the nitrogen down lower than ever before.

Frustrating.

I believe nitrogen is slightly more available at lower PH.... I just found this. See what ya think.

Nitrogen

The form of N and the fate of N in the soil-plant system is probably the major driver of changes in soil pH in agricultural systems.

Nitrogen can be added to soils in many forms, but the predominant forms of fertilizer N used are urea (CO(NH2)2), monoammonium phosphate (NH4H2PO4), diammonium phosphate ((NH4)2HPO4), ammonium nitrate (NH4NO3), calcium ammonium nitrate (CaCO3+NH4(NO3)) ammonium sulfate ((NH4)2SO4), urea ammonium nitrate (a mixture of urea and ammonium nitrate) and ammonium polyphosphate ([NH4PO3]n).

The key molecules of N in terms of changes in soil pH are the uncharged urea molecule ([CO(NH2)2]0), the cation ammonium (NH4+) and the anion nitrate (NO3-). The conversion of N from one form to the other involves the generation or consumption of acidity, , and the uptake of urea, ammonium or nitrate by plants will also affect acidity of soil (Figure 1).

Figure 1. Soil acidity and nitrogen fertilizers (modified from (Davidson 1987)). MAP = monoammonium phosphate, DAP = diammonium phosphate, SoA = sulfate of ammonia, CAN = calcium ammonium nitrate, sodium nitrate​

It can be seen in Figure 1 that ammonium-based fertilizers will acidify soil as they generate two H+ ions for each ammonium molecule nitrified to nitrate. The extent of acidification depends on whether the nitrate produced from ammonium is leached or is taken up by plants. If nitrate is taken up by plants the net acidification per molecule of ammonium is halved compared to the scenario when nitrate is leached. This is due to the consumption of one H+ ion (or excretion of OH-) for each molecule of nitrate taken up – this is often observed as pH increases in the rhizosphere (Smiley and Cook 1973). Anhydrous ammonia and urea have a lower acidification potential compared to ammonium-based products as one H+ ion is consumed in the conversion to ammonium. Nitrate-based fertilizers have no acidification potential and actually can increase soil pH as one H+ ion is absorbed by the plant (or OH- excreted) in the uptake of nitrate.

Phosphorus

The form of P fertilizer added to soil can affect soil acidity, principally through the release or gain of H+ ions by the phosphate molecule depending on soil pH (Figure 2). If phosphoric acid (PA) is added to soil, the molecule will always acidify soil as H+ ions will be released - one H+ ion if the soil pH is less than ~6.2 and two H+ ions is the soil pH is above 8.2. Monoammonium phosphate (MAP), single superphosphate (SSP) and triple superphosphate (TSP) all add P to soil in the form of the H2PO4- ion, which can acidify soil with a pH greater than 7.2 but has no effect on soil pH in acidic soils. The form of P in diammonium phosphate (DAP) is HPO42- which can make acidic soils (pH<7.2) more alkaline but has no effect on soil with a pH>7.2. The hydrolysis of ammonium polyphosphate (APP), where the P present as the P2O74- molecule converts to HPO42-, is pH neutral and hence any acidification due to adding P can be regarded as similar to DAP. SSP or TSP are sometimes declared to cause soil acidification due to reaction products being very acidic;

Ca(H2PO4)2+ 2H2O è CaHPO4 + H+ + H2PO4-​

but in soils with pH values less than 7.7 the following reaction neutralizes the acidity produced so that there is no net acidification;

CaHPO4 + H2O è Ca2+ + H2PO4- + OH-​

In high pH soils (pH >7.2), dissociation of H+ ion from the H2PO4- molecule will generate some acidity.

Crop uptake of P has little effect on soil acidity due to the small amounts of fertilizer P taken up in any one year – hence fertilizer chemistry dominates pH changes and significant differences in rhizosphere pH have not been observed for uptake of different orthophosphate ions.

Figure 2. Soil acidity and P fertilizers. MAP = monoammonium phosphate, DAP = diammonium phosphate,

SSP = single superphosphate, TSP = triple superphosphate, APP = ammonium polyphosphate.


Sulfur

The form of S fertilizer added to soil can affect soil acidity, principally through the release of H+ ions by the addition of elemental S (S0) or thiosulfate (S2O32-, in ammonium thiosulfate - ATS) (Figure 3). However, the amounts of S added to soil and taken up by plants are generally small in comparison to N.

Figure 3. Soil acidity and S fertilizers. S0 = elemental S, ATS = ammonium thiosulfate, SoA = sulfate of ammonia.

For each molecule of S0 added to soil, two H+ ions will be generated, and these can be balanced through plant uptake by either uptake of H+ (same as excretion of OH- ions) or the generation of OH- (effectively organic anions) within the plant to form alkaline plant material (“ash alkalinity”). Where produce is removed (which is often the case in agricultural systems) net acidification of soil will occur if S0 or ATS are used.

Potassium

The form in which K is added to soil – either muriate of potash (KCl) or sulfate of potash (K2SO4) - has no effect on soil acidification.

 

[RFT]

It is my understanding that the pH down is very stable. And not something the plant uptakes. So while it might be “phosphoric”, P acid is not something the plants eat. So it’s unlikely there is a P overload. Plus, we’d see this issue much sooner wouldn’t we?

Gotta examine the breadcrumbs this conundrum is leaving us... why week 4? Why plateaus in the development? Why no colas?

Granted, this go around it appears the development is going well & colas are forming. But consider me skeptical until getting to harvest.

 

[bunkerking]

I used to think I was smart LOL.

The evidence isnt in my favor at the moment.

Should be proud to be willing to give up past notions.
I love being wrong, if someone can explain and prove the point correctly.

ok back to ur shit & time for another bong rip for bk.

 

[RFT]

Zone 1 is in week 7. It’s pH has stabilized this week (so far). Last week it took the same dip Zone 2 did.

Zone 2 is in week 5. As mentioned in the post above, pH dipped last night after 2 days of stability.

Both zones are set to a narrower pH float. 5.8 target with a 0.6 float.

(normal settings are 5.6 / 0.8 so that the pH rises thru the week and doesnt re-calibrate until hitting 6.4)