Ran across this thread this morning looking for an explanation on the rise of my ph.
I have one DWC with no Hydroton and perfect PH, with 4 vegging plants. And I have 4 DWC 5 g buckets with 6 inch pots filled with hydroton, and seedling. The Hydroton DWC Buckets are rising about 3 points in PH every 8 hours. I'm using GH nutes, and GH PH down.
Im checking the PH with a Bluelab Combo meter.
I'm about to start 4 more 5 gallon buckets and do some experiments soaking the Hydroton first.