How to determine the best return pump?

Oh boy I'm asking all the questions lately. Well I am not versed in sumps and returns yet. I'm getting my first sump set-up and am trying to figure out what return pump I will need.

How is this determined, by the rate of flow out of my corner flo box & the length of my outflow tubing? Is there a way to figure this out before the tank is set-up?

Here are the specs if that will help:

70g cube (30x30x18)
Eshopps RS-100 sump (20g) 24" L x 12" W x 16" H
*includes 1” bulkhead intake, 3’ of 1” flex drain hose

I'm toying with getting a Mag 9.5 pump, but also wondering if I could go lower, say a Mag 7.

Any advice would be great,
Thanks!

 

Go with Mag 7.

I have a mag 9 on my 30 cube with 10 gallon sump and it is valved back so it's only running 60% full flow.

I only used it because it was available.


Either way - be sure to use ball valves to you can control your flow.

You will not be able to push enough water through your overflow box to keep up with the full flow of the Mag 9.5. If you upgraded your overflow or added another one.

 

Thanks for the input, I have read about some reefers that have the same cube using the Mag 9.5 dialed back. I told my LFS I was considering the Mag 7 so I wouldn't have to dial it back much but they said it wasn't enough flow, so I was confused . So, I'm leaning towards the Mag 7 now moreso.

 

I have a 100G display with a 30G sump and use an OceanRunner 3500 which is equivalent to a Mag 9.5 or Eheim 1262.

I think the Mag 7 size, but not necessarily the Mag, is right for your needs. I would look at an Ocean Runner 2500 or Eheim 1260 though as they are both better, cooler, more efficient and quieter pumps.

 

With a 1" drain I'd probably go with the Mag 7 too. I would suggest if you can afford it, to use gate valves instead of ball valves. It's well worth it and you will be glad you did after messing with ball valves for a while. I tried 3-4 differnt brands of ball valves in the past and no matter what I allways had issues getting them to turn at all after a while, nevermind close all the way.

Just my 0.02

 

Thanks for the input AZ & Tak, I will look into those other pumps & also gate valves for dialing back.

 

I always go with an external pump and plumb it to a manifold for future expansions like reactors. You can always dial one down but you can't get more flow out of a undersized pump. Go with the bigger pump.

PVC-Manifolds