Hydro pH

[Rev. Green Genes]

Problem: pH corrections are not behaving logically.

Medium/grow method: DWC, top drip from same rez for seedlings.

Feed: and supplements used: FoxFarm GrowBig hydro, Cal/Mag+, Super Thrive

water source: 5 micron filtered city water, de-chlorinated by sitting overnight.

Strain/age: Northern Lights Auto (Pyramid) two weeks from bean drop

light used: ViparSpectra 450 (200 watt) blurple

Climate: 80 deg. F, 50%H, closet, air extraction and fan.

Additional info:

I already took the seedling out, it only got bad water for a minute, and I flushed it. The bottom leaves turned down, but the new growth is fine. She will live.

The problem is most likely the Earth Juice Double Down, but I wanted to get opinions on whether it could be the nutes too. I made a weak solution, 300PPM or less. The pH was 7, I got it down to 6.8 with one cap of EJ, another cap got it to 6.4, another cap went to 4.

That doesn't work. I calibrated pH pen, and tested with liquid indicator. The pen is close to within .2 accuracy. Dumped the batch, started over. Same problem.

Pop22 thinks that I should not use organics in hydro, but the last grow went very well. I had no problems adjusting pH.

 

[Waira]

:smoking: Green'-- I'm not a hydro guy, so i can't say for sure about the issues, but organic hydro from what I've seen is a challenge,... If Grow Big Hydro'is what you're using, unless I'm mistaken, that's not truly organic,...
...what's the EC/ppm of your water? I looked up the EJ, but they say nothing about it's formulation... also, give each adjustment time to work, clearly you were on the cusp of just right between 2-3 capfulls ,... I used citric acid on my KindSoil grow, same as their Natural Down, and to take 170ppm water from 7.6 to 6.5 was less than 1/4 tsp/gal! This product is likely a phophoric acid-? Check it out,...

 

[Rev. Green Genes]

:smoking: Green'-- I'm not a hydro guy, so i can't say for sure about the issues, but organic hydro from what I've seen is a challenge,... If Grow Big Hydro'is what you're using, unless I'm mistaken, that's not truly organic,...
...what's the EC/ppm of your water? I looked up the EJ, but they say nothing about it's formulation... also, give each adjustment time to work, clearly you were on the cusp of just right between 2-3 capfulls ,... I used citric acid on my KindSoil grow, same as their Natural Down, and to take 170ppm water from 7.6 to 6.5 was less than 1/4 tsp/gal! This product is likely a phophoric acid-? Check it out,...

Thanks for the response.

I did get it adjusted, but it took two days. It is finally stable where it needs to be. I have about decided to change to Remo or Green Planet nutes (on @Fairlynew recommend), and give up on staying organic in hydro alltogether.

Double Down is 5% citric acid, and 10% phosphoric acid, with no dyes.
Double Up is 5% potassium bicarbonate, and 10% potassium hydroxide.

neither are labeled organic. The main part that bothers me is that it seems to random. No problems since January, and all of a sudden it it got shady.

 

[EvilScotsman]

hey buddy i was getting this issue aswell. i use phosphoric acid for ph down. as a rule it brings my ph of 10L feed down by 0.1 per drop but if i put in a couple drops too many it drops massively. i now make sure to mix the solution vigorously and check the ph after every couple of drops. i also check the pen with a bottle of volvic in between checks. this way theres definately none of the higher ph solution left on the sensor to give it a false reading.(mines is covered in some sort of fabric) and lets me know that its still accurate.

 

[Waira]

:smoking:.. with organics, you need a robust, diverse cast of microbes to keep nutes cycling and made into available forms,.. all these biological activities make for increased amounts and complexity of input/outputs as the 'crobes go about their bizz; like root cells, the uptake of ions by microbes often involves the exchange of charge equivalent OH-/H+ as cells seek to maintain both charge and pH balance... in soil/soilless, there are other mitigating components that help buffer and reserve all this, but in an aqueous solution, that's not the case, to say nothing of the different availability dynamics vs. soil/-less media,....hence the organic challenge of hydro!