water flow?

[StirCrazy]

first is your tank drilled?

Personally I would go about 10% of the tank volume through the sump. you can go more but do not try to get all your flow through your sump.

the reason I say this i because you are going to be running heaters, skimmer, ect from your sump and they all need a bit of dwell time, so if your water flow is to fast your heater will be on more than it should and if the sump turn over is to fast your going to reduce the efficiency of your skimmer (depending how it is set up), ect.....

if you don't like power heads you could look at adding a closed loop set up also.
go MH from the get go as it will alow you to keep anything instead of just some things.

Steve