closed loop question

[EBR]

Hey Everyone --

I've recently stumbled upon quite a few mentions of a "closed loop" setup on this and other forums. What exactly is that? Best as I can tell, it looks like nothing more than a pump (say, in your stand) that sucks water from near the bottom of the tank, and squirts it back in near the top through several outlets, all plumbed with PVC. Ones I've seen pictures of don't seem to have filters either -- just seems like a single purpose device that helps to circulate water. If that's the case, is there any advantage of this over a few powerheads? It certainly provides a cleaner look (no power cords, nor PHs in the viewable area).

Thanks.
Matt

[fishfreek]

Thats exactly what a closed loop is. Soly for the purpose of water circulation. Usually its on large systems where you would need many many powerheads to get equivlent flow. The intake and return can be anyway within the tank. (does nto have to pull from bottom and return to top).

Its called a closed loop because at no point is the water open to the air.

[EBR]

Very cool -- thanks. I'm just about to the point where I'm ready to upgrade from my 55 to a 120. This is something I'll definitely work in.

Thanks again.
Matt