Water issues

[RugDr]

I’m dipping my toe in DWC. So far, it’s a pain the butt. I finally feel like I’m getting everything squared away but am battling a weird issue which I can’t seem to find answers to.

I have a tote converted to seeding starter. With only a single, week-old seedling dropping roots into 3 gallons of nutes. I am using RO water. GH flora series super diluted (150 ppm). My RO comes out of the tap at perfect ph. 5.8. I put it in a bucket and let sit and the ph doesn’t move. Then I add nutes and it holds. Then i put in the tote with air stone and it starts climbing fast. In just a few hours it’ll be at or over 7, I correct back down to 6 next morning it’s up to 7.3, correct back down and it starts climbing again throughout the day. I’ve replaced the nutrient mix 2 times in just a week trying to get this ironed out.

I’m reducing ph with vinegar for now. Just a couple tsp for 3 gallons brings it right down. I have GH ph down on the way. I’m super frustrated and thought RO was supposed to be easily ph balanced.

I let a sample sit in a bucket during the same time and sure enough ph doesn’t move. The only variable is air stone/oxygen Should I really be adjusting ph that much 2-3 times per day?

 

[BedroomFarmer]

Try ph up/down made for hydroponics/growing.

 

[Bobthe420Builder]

And oxygen will for sure effect your balance

 

[TurboBucket]

The air stone is causing the accelerated drift, not having a stable pH down product also causes the cycle to occur faster. Stronger acids like citric, or phosphoric, last longer keeping pH stable longer.

 

[RugDr]

Looks like I’m headed to get some battery acid. PH down is 2 weeks out. Battery acid is a lifetime supply of ph down for 15 dollars.

 

[Justin Goody]

Using pH down (I use citric) instead of vinegar will be a huge help, and using drops as opposed to teaspoons will be more cost effective as well.

 

[RugDr]

Just mixed a batch of ph down from battery acid available at any auto parts store. 1 part acid to 19 parts water. 17.99 buys enough acid to mix 23 gallons of ph down. Hopefully this is more stable.

 

[Bob Loblaw]

I'm kinda a dummy at all this but I did read somewhere that battery acid can have some unwanted additives in it, not all but some can.

 

[Bob Loblaw]

Also your medium, did you buffer it?...or maybe that don't matter in DWC.... just thinking out loud.

 

[RugDr]

Wow. Vinegar was bad news for me. PH was at 7.5 again in just 3 hours. I read all over that folks were using it to ph down. It gave me really milky water in just 24 hours. I dumped it and mixed a fresh reservoir.

New batch:
RO water sitting since yesterday. Starting PH was 6.3 added nutes (GH trio to 150PPM) and lowered ph to 5.8 with 2 teaspoons of diluted sulfuric acid anticipating a climb.

We'll see how much it wants to climb after it's been bubbling with nutes for a while. I was planning to keep an extra bucket on hand but it's looking like i'm gonna have it aerating so I have stable water for top off/res changes. When i have that running i'll be interested to see if the PH rises without the nutes. I suspect my issue is unrelated to the nutrients.

If this is all true it means my RO water has a 1.5 ph increase when adding just 150 PPM nutrients and an air stone. That sounds reasonable to you guys with experience?

 

[RugDr]

Also your medium, did you buffer it?...or maybe that don't matter in DWC.... just thinking out loud.

I'm using soaked/rinsed clay pebbles but i'm not top feeding at all so the medium isn't running off to the res.

 

[RugDr]

I'm kinda a dummy at all this but I did read somewhere that battery acid can have some unwanted additives in it, not all but some can.

I saw someone mention that as well but i'm not sure it's always true. Mine says sulfuric acid and water on the ingredients.

 

[RugDr]

Climbed back to 6.7 corrected to 5.6 hoping i can finish the yo-yo soon. The correction took less acid this time so maybe we’re getting somewhere.

 

[Northern Hydro]

Is it possible you have a light leak ?

 

[RugDr]

Is it possible you have a light leak ?

Yes. The tote is clear sided but wrapped to block most of the light. I was just hoping to them through seedling stage in this before moving to buckets. The top is solid. Any light would be minimal. No signs of algae. They are under a 20,000 lumen led. What would light leaks do to to ph?

 

[Northern Hydro]

Increases ph in my experience .. I dunno just thinking of all possibilities . I use GH trio and ro and rarely have ph issues ? Hope it works out for you! namaste

 

[RugDr]

Increases ph in my experience .. I dunno just thinking of all possibilities . I use GH trio and ro and rarely have ph issues ? Hope it works out for you! namaste

Algae/scum growth in your experience? You got me thinking. There was a pretty big bloom of something that liked the vinegar in the res before I swapped it. I suppose something could be consuming the nutes but so far the roots are pure white and the water is clear. I just checked again. The Ph rose to 5.9. I left it alone. We’ll see what tomorrow brings.

 

[RugDr]

Ph appears to be stabilizing. It climbed to 6.1 overnight which is way less than in the past. If these girls survive me it'll be a miracle.

 

[FatBeaverBuds]

I find my pH is most temperamental early on in the growth cycle and becomes more stable as the plant grows. I'm not sure why. Probably due to nutrient strength and more nutes to buffer the pH.

 

[Northern Hydro]

You are using cali/mag in addition to the GH tri with ro water, right ?

I agree with Fat beaver ..could be that there isn't enough of a canopy for a light leak? Or ? I dunno, I just dropped a bean and fought with my ph for about 24 hours , could be the dirty bucket , could be light , who knows ...stable 3 days in now thou

It's a weed ...pretty hard to kill ..you will get there