Originally Posted by
crackers
I would think that if all your test are coming out fine, then why would you need to replace water at all other than to refil due to evaporation... am I wrong by thinking this?
IMO yes, you are wrong not to do water changes. Even if everything isa good, water changes make it better! I change out 20 or 30 gal out of my 150 biweekly so things remain good. Especially if you have corals, changes put back lost essential elements. Do you test for calc and ask? If you don't, and have corals, you would be doing them a favor by at least monthly water changes.