I have a 200 gal tank and I use a Calcium reactor for Calcium and alkalinity. At first I thought this was causing my low pH so I turned it off for a few days. It made no difference. I replace about 3 gal of water per day that is fully saturated Kalkwasser. I had it controlled by my Apex to only come on at night but that caused the level in my sump to vary too much which kept messing up my skimmer.







