Ok so I got some of this stuff called bio enzyme a yr supply I have been using it for a few yrs and I must say it is awesome I have periodically checked water levels and still very good this stuff reduces water changes up to a yr in ur tank did I mention I love this stuff I change my water once a yr now in my 55 gal tank now
What about replacing trace elements though. Water changes aren't solely for keeping nitrogen elements In check. We have to maintain calcium, magnesium and all those in line too. I'd pry only use it on a FOWLR.