What is a Powerhead?

[saltyfish]

What does it look like? Is it like a pond pump in design? I'm starting my tank for the first time and I'm looking online but I don't think I'm getting the item that I need. If you know a good websight that is cost compeditive than please point me in the right direction.

 

[richard rendos]

Look here:
<a href="http://www.championlighting.com/e/env/0001-762360-3477905176-229088172-6841-5m1J6/Products/Pumps/pumps.html?link=/Products/Pumps/mj.html" target="_blank">Power Head</a>

 

[bluemarlin]

A power head has a small motor, an inlet and an outlet. Historically they were used to power undergravel filters. The power head is positioned on top of the lift tube and sucks water down through the gravel bed and up the tube. Then, the power head simply blows the water back out into the tank via the outlet. Out lets can be positioned to spray the water in any direction and from side to side. On some models the power is adjustable and on others the flow is reversable.
Today, powerheads have evolved and though still used to work undergravel filters they are used in many aquariums for the simple act of moving around water. Some clip onto the top of your aquarium around the rim. I hope this helps.