Hi guys....been using my Coralife 12X for almost a month now and would like to add some feedback. My fishes are now more active and i do not get white spot since then. The color of my water has improved alot. Yes, there are some disadvantages like it kills some good bacteria but on the whole it also kills the bad ones. End result my fishes are better with it on for a set time. My hours of operation is around 3-6 hours a day. Cheers.....just my 2 cents worth of thoughts.

MadZ