Hang in there and keep checking and experimenting. I use ProMix HP which is peat based and it does lower the ph in the medium a little. I've also used Ocean Forest but can't remember how much it affected the ph. If you can check the ph of your runoff that would be very helpful.
grey1223 Reviewed by grey1223 on . Raising PH Hi All I'm am using Fox Farm Nutrients at 1/2 their recommended dosage. I have no problems with the PH until I add the Open Sesame. This tend to turn the whole mix in to straight up ACID. PH 4.0 or Lower. I am using a General Hydroponics test kit, and am having to use a large amount of PH up to get it to 6.0 or better. The PH up contains potassium carbonate and potassium silicate. Should I use some dolomite or something ,to up the ph instead of overdosing the potassium? Rating: 5