scotkis, make sure your overflows are able to handle the pump. put a ball valve after the pump exhaust, to be able to adjust it accordingly.
i don't know about anyone else. my main goal is to keep the water clean, and aerate it.
if you don't have sufficient flow, you are going to have detrius buildups here and there, and that's where you are going to run into some trouble, in the form of algae, or cyanobacteria.