Eseoteric_grower is on track, the PH rising is likely due to an infection.
One suspect is Cyanobacteria (blue algae), are the roots slimy to the touch?
Also called root slime...
Basically suffocates hydro plants they look like this. Eventually the res turns to a slimy mess...
We need more info... have you been using H2o2?
Did res temps rise, air pump die?
Are your air stones suitable for the volume of water in your buckets?
- Cyanobacteria is actually a aerobic bacteria so airstone actually feed the bacteria.
Great white is a mycorrhizae product that’s overly expensive for what you get...
Once a mycorrhizae colony has built up on the roots you don’t need to add it again...
Hydroguard is better option for a healthy res tank. And cost effective...
You can chat in the comments just link
@PharmaZ