what is the best and easiest way to raise pH? Ok, some history. I've known about chronically low pH in my systems for a while. I thought I could overcome the issue by keeping other perameters (especially alk) in check. I would have thought that there is adequate ventilation to the water surface but that's the first thing I'll check. A local lfs suggested using an air pump directly into the sump or return chamber. Currently I'm testing pH every few hours and through the night to get a baseline. My friends at Amazon are sending me an air pump. Should arrive tomorrow. If the increased air from inside works then I'll just place some fans. If not, I'll pipe in air from the outside. So far today 3 tests have shown about pH 7.7.