I use a five stage RODI system and mix in Instant ocean, reef crystals; let it mix for 24 at least. In the sump I have a live rock, a BRS Carbon reactor and a BRS GFO reactor along with a ATO system. It is a new system so I was not to worried about it but now its been two months. I don't dose or add any chemicals. I did use epoxy to glue down my rockscape which I read makes the skimmer go crazy but again its been over two months.