I want to add a small powerhead to my 55g display tank. Mostly, I want it just to create movement along the back/bottom of the tank behind the live rock. It's hard to "vacuum" back there, and probably is a cesspool by now... I don't expect wave action, and I don't want to pay a lot.

Hopefully too, it is something I can buy locally? I know you can't answer that last part, but I just mean "standard brand" stuff. Koralia Nano? Tunze NanoStream? Better choices?