A sucessfull sump for a saltwater aquarium?

Question:what do you need in a sump for a sucessfull reef aquarium?
thanks

Answers:
you do not need a sump.A lot of people use the for reef and for fish only tanks but it is not required on either it is a matter of preference.But you do not need one.If you have one I would use live rock rubble as a filter and not bio balls.I do use a washable filter in my sump.I remove it every so often and was it and replace.I have live rock in one side of the sump and my pump and heater in the other side.I have macro algae in my over flow..
The best thing for a reef tank is lighting and water flow as long as you add power heads you will be fine..