just curious who uses gfo and how often. Do you use a less than recommended dose for your tank size? How old is your tank? I had been running 3/4 cup high capacity gfo 24/7 through a BRS dual reactor as recommended by their reef calculator but I was stripping my water, well at least according to my Hannah checker and my corals. I recently changed it to 30 min on 30 off with about 1/3 the recommended amount and I am still at 0. I may take it offline for a bit and see what I end up at naturally. Tank is still new. Just about 1 year old mixed reef 100 total water volume. I’m hoping it doesn’t swing the other way too fast and anger the spa corals with dirty water.