Chasing ph

I have found that too high nute ppm can cause ph increases. Try cutting back on ppm and see what happens. Incorrect ph is a critical issue for plant health. You need to fix it

 

What's the ppms and pH of your tap?
Do you trust the accuracy of your measurements?  
 
You don't need to set it out that long. A little chlorine won't hurt, but if your tap is full of other crap, well... you may need to filter or something.
 
Did you condition the rockwool? Soaked in 5.3 pHed water for 12-24 hours?
Rockwool is naturally slightly Alkaline. Hence the need to condition it.
 
You shouldn't need to be adding stabilizers or the like. I'd change out the res, lower the ppms a little from wherever they're at now.
Set the fresh res at 5.3. I say 5.3 to help force the internal pH of the rockwool down quicker. Don't go lower than 5.3.
Monitor the rise and adjust back to 5.5 daily if swings over 6.5.
If it stabilizes around 6.0ish, leave it alone. Just pH your top off to 5.8. Then adjust the res to the same, after topping off.
Only ever adjusting again if it swings over 6.5.

 

just flush at 5.8 imo
 
and as the others said, ensure you're at the right ppm for your plants
 
if solution is too strong, the plants eat more water than nutes which in turn makes ppm rise and will alter ph
 
there's absolutely no reason you should have to ph your res directly.
 
also, make sure there is enough DO in your res

 

Agreed, while you don't state your nute strengths, too high will cause pH drift due to imbalanced uptake.
However, I've not seen a hot solution raise the pH as much or as fast as stated.

 

indeed
 
something else is surely off

 

What root supplements are you using? Add some silica blast 2ml per gallon if you already haven't, it will benefit your roots and stabilize your pH.

 

adding more junk will help??
 
not sure about that

 

Silica is not Junk, in fact it's the first thing that should be added to any Hydro type system. Many growers neglect the root system, research silica and decide for yourself. I've used it for 6 years.

 

i've never used it

 

The equivalent GH product is armor Si

 

I use silica, but silica isn't going to fix his problem right now.




Chef.

Head Chefs Indoor and Outdoor Adventures - http://forum.grasscity.com/index.php?/topic/1289059-Headchef%27s-indoor-and-outdoor-adventures

 

It may not completely solve it, but it will head off more serious problems later.

 

To lower ppms: remove some solution and replace with water. Or just top off with water if the level is low.
To raise ppms: add nutes. 

 

No worries we've all had our moments...