power heads

[mm16]

I have a 45 gallon bow front tank with live rock, how many power heads should I have?

 

[Northstar24]

You're looking for anywhere from 20-40x your tank turnover in volume, so you would be looking for anywhere from 900-1800 gph in total flow.

I would suggest at least two powerheads (one on each side pane) but more important than total flow IMO is RANDOM flow. My tank really took off once I got rid of static flow in favor of some random, chaotic flow

 

[mm16]

I put 2 power heads in totaling 1650 gph. I faced one down and the other straight across the tank. But the one that was facing down made a valley in my sand. I was told to face one down and the other to the top of the tank, is that what I should do. I really don't like what it did to the sand.