from what i have seen the algae in the tank is what is most important. i have thought about trying them but my water is to soft and i have no way to up it cause i use sponge filters so cant put chips in them lol. if i do decide to try them i think the first thing i will do is plant and lots of rocks with light on alot for extra algae to grow. sorry for hijacking but just trying to figure it out as well before i try. can any one chime in?