Before you buy a return pump I want to let you know something some will agree and some will not. It comes down what you think is best for your tank. Im not sure what the gph
on a mag 9.5 is but let me give you some information before you make a decision. What i have read, researched and live by, lol. At first I figured my turn over rate from my dt (display tank) to my sump needed to be as many gph
as I could afford. But that entirely true unless you are running a wet/dry filter. You really only want your dt to cycle through your sump 3 to 5 times over. The reason why is contact time for your skimmer and other equipment. This gives them time to do what they need to do. I understand when you wany your water to rush all the junk out of your dt into the sump but if its rushing water through so fast is your skimmer having time to pull ot out? Prolly not. So if you slow the turn over rate from your dt to sump to around 5X's your tank volume your skimmer will have time to do its job with more efficiency. Now to make sure you understand the turn over in the dt is different from the turn over from your dt to your sump. This can be confusing at first. Dt only turn over rate fowlr
(fish only with live rock) 15-20x water volume, softies 20-25x, lps
25-30x and sps
30+ water volume. This is where your powerheads are used for. I have recently added the knock off jebao wp40's to make tank and love them you will only need one and for 100 bucks is a great price for what it can do and when compared to the mp40's for 450 bucks.
To make sure you know:
Dt to sump=55 x 6= 330 gph
maybe a little more for elbows check or ball valves so up to 500gph should work for 4ft head.
Dt only=55 x 20= 1100 gph
to 1650 will give you a decent water movement I think.
When finding a powerhead find one with a magnet it will save you a headache and keep in mind the jebao wp 25 or wp40 is around a 100 bucks and other powerheads are close to the same price and do alot less. They are worth it. But it mainly comes to what your prefer. You also may want to invest into a rodi
unit if you dont have one. Bulk reef supply is a great buy. My friend has an ebay deal which saved him 100 bucks he hates it.