carbon and impact on PH

[Doug]

I have never heard or seen carbon have an effect on ph. At least with good carbon. I use it 24/7. Always have.

PH, is more oxygen/co2 related. I dont believe in the skimmerless view that powerheads on the surface alone, can replace skimmers or overflows for creating oxygen/co2 exchange. Airstones or powerheads pushing water from bottom to top can.

My ph with nothing else changed is;
8.0 to 8.1 with the skimmer & overflows off.
8.1 to 8.2 with overflows running but no skimmer.
8.2 & up with skimmer & overflows in operation.

Also needed for good ph control is a decent steady alk. level. The addition of a 2-part, like B-Ionic, C-Balance or Kent 2-part can help. Also the regular addition of kalkwasser to replace evaporated water will help. Should be added slowly at night when ph is lowest. Kalk has a ph of 12.