Return pump question

[patsfan1130]

I use an external overflow on my F/O tank & use a 20 long sump. The ovverflow has a 1'' bulkhead. What is the standard flow rate for these? 400...500 gph?

I currently am using a RIO 2100 with a 3/4'' return and I want to switch out pumps. I am almost positive on the Mag due to it's reliability and relative quietness. I believe the RIO pumps around 375 gph @ 4' head and it seems to work fine. I like the Mag 7 with a rate of 450 gph but has a 1/2'' fitting. The smallest Mag with a 3/4'' fitting is the 9.5 with a rate of 800 gph @ 4'. Do ya think this is overkill? I dont want a tidal wave in my tank.

I guess once I am sure what the flow rate of my overflow is, I will be able to make a more educated decision.

Thanks,

Mark

[Poseidon]

My overflow uses 2 1" pvc drains, and I use a MAG 12 for a return pump. I also use 1" PVC on the return. If you read the directions on a MAG it states that for "best performance" use 1 1/4" PVC!!! Holy cow, why do they only put on a 3/4" fitting then? It is because to move that much VOLUME you need a larger pipe. It will just move at a slower VELOCITY. (Which is a good thing.)

I think as long as you put a ball valve on BOTH the return and the overflow you will find a balance simply enough, no matter what pump you choose. I'd go with at least the 9.5 though!!!

[acropora]

I use an external overflow on my F/O tank & use a 20 long sump. The ovverflow has a 1'' bulkhead. What is the standard flow rate for these? 400...500 gph?

I currently am using a RIO 2100 with a 3/4'' return and I want to switch out pumps. I am almost positive on the Mag due to it's reliability and relative quietness. I believe the RIO pumps around 375 gph @ 4' head and it seems to work fine. I like the Mag 7 with a rate of 450 gph but has a 1/2'' fitting. The smallest Mag with a 3/4'' fitting is the 9.5 with a rate of 800 gph @ 4'. Do ya think this is overkill? I dont want a tidal wave in my tank.

I guess once I am sure what the flow rate of my overflow is, I will be able to make a more educated decision.

Thanks,

Mark

Mark,What size tank do you have.I see that you are looking for a 3/4" output on your return pump.The Gen -x 2400 has a 1/2" and 3/4' out put at 635GPh.The next model up,Gx-4100 is 1085 GPh. Both of these pumps come with a control on them to slow down the output flow.When you look at pump ratings you have to also consider loss due to head pressure. The distance from the floor to your tank as well as the use of elbows and Tees will dramatically reduce the water flow.You can restrict the out put side of most all pumps without negative effect,so the output size is not a big issue. You can always adjust the plumbing size with PVC bushings to match your application.