pH migrates like geese in the fall

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MootPointBlank

Murphy's Law Incarnate
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I keep adjusting my pH down everyday by at least 1point. Using BMO Grow it Green and Super Plant Tonic, which are naturally acidic. Plants are in Hydroton pellets in custom DWC setup. Will the Hydroton cause this migration toward alkalinity? Should I be pH correcting them before I use them? Reservoirs are Rubbermaid tubs and the rest of the materials are PVC and an airstone.

Thanks,
MPB
 
What can happen is this...your nutes buffer the ph as well, if plants are eating a lot(nutes) this will cause ph to climb as there is now less nutes to buffer mix. If they are drinking a lot this will leave a higher concentration of nutes...lowering the ph. Not saying this is happening cause there is not enough info. Algae and other bacteria will also cause ph to rise as they feed on your nutes. I too am unsure what you mean by 1 point. When I was doin res' I would let ph drift up from about 5.2 to almost 7 before I adjusted to insure all nutes were available. Your plants uptake diff. nutes at a greater rate with a slight variance in ph. There is lots of great people here to get you through it...no worries.
 
Budders Keeper said:
What can happen is this...your nutes buffer the ph as well, if plants are eating a lot(nutes) this will cause ph to climb as there is now less nutes to buffer mix. If they are drinking a lot this will leave a higher concentration of nutes...lowering the ph. Not saying this is happening cause there is not enough info. Algae and other bacteria will also cause ph to rise as they feed on your nutes. I too am unsure what you mean by 1 point. When I was doin res' I would let ph drift up from about 5.2 to almost 7 before I adjusted to insure all nutes were available. Your plants uptake diff. nutes at a greater rate with a slight variance in ph. There is lots of great people here to get you through it...no worries.

I absolutely agree and have found the same information elsewhere. However, there are only three fresh clones with hardly any roots yet, sharing a 4gal res of fresh nutes. I'm thinking that their affect on nute concentration is probably negligible. From what I can see inside the res, which is damn near lightproof and sits at 70F steady, there doesn't seem to be any other growth. I adjusted again yesterday to 5.2 and will check again in a little bit when the light is on. Have you heard about or experienced Hydroton raising pH? Just wondering if I should have pH adjusted before using. I also should have cleaned some other parts a little better, there is a sudsy-looking foam in the res that has the look of soap, but I've heard of this happening before when using organic nutes, so I'm not too concerned about it, but it could be soap.:confused2:

Thanks,
MPB
 
Budders explained it well.

Depending on how big your reservoir is, and how fast your plants are growing, you may find yourself needing to adjust your tds/pH more often than you originally expected.

A little pH drift is natural, and good. What's the range you're trying to keep it in?
 
King Bud said:
Budders explained it well.

Depending on how big your reservoir is, and how fast your plants are growing, you may find yourself needing to adjust your tds/pH more often than you originally expected.

A little pH drift is natural, and good. What's the range you're trying to keep it in?

5.2 to 5.8 seem to be the optimal uptake ranges according to the majority of the resources I've found.

MPB
 
Growdude said:
Did you rinse the hydroton well? Ive seen the dust cause the Ph to rise.

Yep rinsed and let soak for a few hours in tap water. Could it be the tap water leeching out of the pellets?

Just checked pH again and back up to 7.05. Now in the process of lowering it again.

MPB
 
sudsy-looking foam
Does this have a smell to it?
which is damn near lightproof and sits at 70F steady
IME near light proof isn't enough. Just having the white 1/2 in tube in the light for 6 in was enough to give my e&f res. algae/bacteria/foamy yucky stuff. I did read that the nutes were freshly mixed. Hmmmmmm?... ooh, were the nutes sitting around for long before used? Just a note you probably know, organic nutes have a tendency to get alg/bac easier.
Does it ever stop rising at a certain point or just keep on goin off the scale?
 
Budders Keeper said:
Does this have a smell to it?
IME near light proof isn't enough. Just having the white 1/2 in tube in the light for 6 in was enough to give my e&f res. algae/bacteria/foamy yucky stuff. I did read that the nutes were freshly mixed. Hmmmmmm?... ooh, were the nutes sitting around for long before used? Just a note you probably know, organic nutes have a tendency to get alg/bac easier.
Does it ever stop rising at a certain point or just keep on goin off the scale?

Unfortunately I've no way to further tell how lightproof the res is other than the opacity test of holding it up to one of my grow lights. As for algae/bacteria, I don't see any lifeforms in the tank, just foam which I think could be from the airstone blowing bubbles through it all the time. I know that my nutes are living cultures of microorgs so it could also just be their respiration. The nutes are brand new as well and have a lot left of their shelf life. Since I check the pH everyday, several times a day now in my efforts to correct it, I couldn't say how high they might go if left alone. I think that the levels I find it at when left overnight are probably the maximum, an unlimited rise in pH would indicate a severe oversight on my part about using some material or another in the construction of the res.

I don't know, it's frustrating.

Thanks,
MPB
 
Shockeclipse said:
Your ph shouldn't be that low. I range mine from 5.6-6.1. 5.8 should be optimal.

It seems to be stabilizing ~6.4. Plants look splotchy and sickly yellow with brown spots interspersed across the leaves and the stems are eggplant purple. I don't think they're supposed to be that purple. Last I checked, the roots were coming through okay and heading toward the res. I don't think I'll adjust the pH anymore because I think I've shocked them enough.


MPB
 
#1 - Use panda film to cover your reservoir. My water has stayed crystal clear this grow. As for as the ph heading up, get used to it. I rinse the holy heck out of my hydroton and mine climbs every grow for the first few weeks until it stabilizes. I rinse with crappy city water which could be the issue but the ammount of RO water needed would be ridiculous. I do use RO water for my ebb and flow exclusively. Once I hit flowering, my ph barely goes above 6.15. Once I add more h2o with pre-mixed nutes, it lowers to 5.8-5.9 which seems perfect. I do think the whole deal is the poor quality city water used for the rinse. Next time I may do the rinse in city water but let the hydroton soak for a day in RO water. If anyone has tried this with success, please chime in.
 
I was having ph issues for a while too, because I was changing out each res and not letting the nutes mix all the way. I just built myself a little mixing station so I can add nutes to ALL my water, adjust ph, and let sit while a few airstones mix it around for a day. Then adjust ph as needed and change out buckets. I just used a 30gal tote, built a stand (sits around two feet off the ground) and put a valve on it to drain. I will throw pics of it up in my GJ tonight.
 
you want your ph to drift a little(5.5-6.1) so it can absorb more nutrients... if your ppm is stable, and your ph is going up that is a good thing.
 
Mr. Moon said:
you want your ph to drift a little(5.5-6.1) so it can absorb more nutrients... if your ppm is stable, and your ph is going up that is a good thing.

Understandably so, but I just threw new nutes in yesterday at 4.7 and it "drifted" overnight to 6.5. PPM isn't changing because plants are so shocked by pH shift, they're struggling to stay alive. Gonna try adjusting down just a little bit tonight and then again tomorrow, but I don't expect it to work.

MPB
 
Just checked again and it's still at 6.5. The pH down I have is obviously crap. I'm ordering GH up/down and the Canna Aqua nutes now. The plants are really suffering now and I don't expect them to last much longer. Just for s**ts and giggles I threw a slice of lime into the res in hopes of having a sustained release of citric acid. I'll check it in a little while and see what happens.
 
Woah woah.. don't go all out ordering a bunch of things just yet, it's possible you're making a mistake somewhere in the process. :X
 
King Bud said:
Woah woah.. don't go all out ordering a bunch of things just yet, it's possible you're making a mistake somewhere in the process. :X

Thanks, but which process and what mistake might you be anticipating?

MPB
 

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