Low pH with kristalon brown

[967]

I've been using kristalon brown recirculating for a few months now and the pH drops to high 4's to 5 constantly. Have read another thread someone complains about exactly this. What do people do to combat this issue? Or is it really a non issue just keep throwing pH up at it? That's what I've been doing and plants seem perfectly fine, but would be nice to not have to

I have a top off res I adjust to 6.5 but it still drops. I know a fair few people rate this stuff I'm wondering about other people's experiences in regards to this.. ?

 

[Creeperpark]

I've been using kristalon brown recirculating for a few months now and the pH drops to high 4's to 5 constantly. Have read another thread someone complains about exactly this. What do people do to combat this issue? Or is it really a non issue just keep throwing pH up at it? That's what I've been doing and plants seem perfectly fine, but would be nice to not have to

I have a top off res I adjust to 6.5 but it still drops. I know a fair few people rate this stuff I'm wondering about other people's experiences in regards to this.. ?

It's important to stabilize the pH with cal mag before adding fertilizers.

 

[Orange's Greenhouse]

I have seen that before. My current theory is that root exudates are acidic and so abundant, that changes reservoir pH. Other mechanisms such as microbial growth and nutrient uptake can increase pH but are not strong enough to tip the scale towards high pH. pH is just the sum of all effects. I admit that is a bit hand wavy.
Adding pH down is the best thing and only thing you can do. Roots perform best at a specific pH and how it gets there is not too imporant.

Calmag will do the opposite. The main constituent is calcium acetate. As calcium gets uptaken a hydrogen ion is expelled, both are positively charged and the net exchange is 0. Acetate plus a hydrogen ion is acetic acid. Acetic acid lowers pH. Roots do not absorb acetate.
It's also the reason why Calmag often alleviates problems that are not down to fertility but are in fact caused by high pH.