closed loop question

[Booboo33062]

instead of using a closed loop system in my tank wouldn't power head add a current in the tank? I can't drill the tank, because I was told it would void my warrenty. I thougth I read somewhere that the closed loop pvc was ran under the live rock and kept it all clean underneath.

[Casey]

Powerhead will work but they are ugly and weak,you can do a closed loop over the back of the tank and dont have to drill