I tested PH of some run off from my plants

[Elliot Jansen]

And I found the some of the juices squeezed out of the rockwool were far higher than I had expected. She was aobut 3 -4 weeks into flower. But I was wondering if the plants uptake of nutrients causes the PH of the saturated block to drift upwards, and if so should I be using a lower PH in my flowering nutes to maintain 5.5 - 5.8. I am using Botanicare products if that matters at all.

 

[4u2sm0ke]

:bump:

 

[buddog]

whats up jansen i had that problem on my first grow. i could pull a sample out of the rockwool and it would be up in the low seven's on the ph. the only thing that i think happen was that i did not soak the rockwool long enough in ph water.And what made me check it was the ph in the res. kept going high.But it should slowly come down .

 

[jrobertson]

We use rockwool all the time, run at 5-8, we stay at that ph all the time, they say that if you follow this rule its fairley accurate.
1 ppm goes up, ph goes down, less nutes
2 ppm goes down, ph goes up more nutes
3 ppm stable, ph up good thing, so watch your plants and use that as a guide carefully. Hope this helps. bye for now