Can't keep pH under 6.4

[islander420]

I'm sure it's the hydroton causing your PH to drift up. I have the same things happening to me in Perlite. I just keep adjusting daily when I top off my res. ( I adjust both my new nute mix and res mix after it has been topped off.) You should be fine. Just keep adjusting daily to keep everything in check.

 

[rrog]

I hear ya, but most hydro growers are not adjusting in between nute changes. I just change nutes every week or two depending on what's growing. If I add back RO to flush, then sure, there needs to be some pH adjustment.

I'm really hoping the new Hydroton works out. I'll be running some pH trials before using it. This wouldn't be so bad, but I use a lot in my drip system.

 

[TanzanianMagic]

RROG,

Glad to hear you harvested your plants.

I would just like to add - the procedure is that you allow all the extra salts in the hydrotons to lose their ability to buffer to a higher ph.

Ph the water to 5, let it stand for a day or two, and then come back and add acid again to achieve the desired ph. This should be done until you have a much more stable and low ph.

The same should be done with rockwool and apparently perlite too.

Flying high

 

[Ganjagrower1]

I think you want to add your nutes in before you start to ph the water. because your nutes usually drop the ph in the water.

 

[rrog]

Hi guys. Thanks for the responses. The "hydroton" that I'm using is 6 months old now. Still a pH issue. It's been continuously bathed in 5.6pH nutes the whole time. If it was going to ease up, it would have by now. If I go continuous drip, pH will go up much faster than if it's a 4x a day short drip. Definitely the stones.

I mix all nutes, then pH.

I would have thought I would have successfully leached out all pH basic materials by now, but that's just not the case.

 

[Ganjagrower1]

what kind of nute are you using. most nutes have a ph stabilizer in it. I think duh... i have a blank right now. I know gh does for me any way.

 

[kaljukajakas]

I would have thought I would have successfully leached out all pH basic materials by now, but that's just not the case.

Everything inorganic that messes with pH really should have leached out in 6 months, unless you have magic hydroton...

Could it perhaps be a combination of fast nutrient uptake and something growing on the roots/substrate?

To test you could take out a little hydroton and nutrients and put them in a cup, add a bunch of hydrogen peroxide to kill whatever might be living there and then start monitoring the pH. You could do another cup that's boiled first. If the hydroton is at fault a quick boil should cause a rise in pH as more stuff leaches out. If there's nothing to leach out and the pH climb is something continuous (bacteria, nutrient uptake) then the pH should stay pretty stable after it's been boiled.

 

[rrog]

All good thoughts.

It's generic Hydroton that I bought in a brown box. No root rot. It's the hydroton. I've tested the hydroton by itself and watched the pH go up. Unusual, yes. But that's what's doing it.