It works like a champ...LOL...but like Nyles said, a healthy tank does not need it...I would say should not relay on it, but I think with a big skimmer and small weekly dosing and cycling those, could be an extra source of health in our tank...I mean, we have phosphate remover, carbon, purigen, skimmers, zeo, etc...I think that since we are trying to keep a piece of the ocean in our home, but lack alot of what the ocean offers, including the water volume, everything helps and this is just another thing to add to list...