I think its just one of those products that doesnt actually do anything but rid you of your hard earned cash, for really clear clean water, its best to do water changes (once the fishless cycle is finished of course) and add filter floss to your filter to grab all those fine particles that can sometimes float around. Having said that Ive never used it so cant say for sure, but then I never buy any of those sorts of products, the only thing I add to my water is dechlorinator.