Return pump question

[spleify]

Hello all,
I am in the process of setting up a new 24" cube, approx 60 gal.
I will be running an external overflow that is 23w x 9h x 4d. I will have about 5 1/2 feet of head pressure. I'm guessing I will probably need a pump rated for about 600 - 700 GPH.
I will be running a a closed loop with an Iwaki 40, for about 1300 GPH.
I would like to know what pump you chose and you're reasons for it.
Thanks for all the help.
Spleify

[wife no likey]

that is very similar to my setup - 60 cube w/ external overflow and running a CL.

Personally, I would use the Iwaki for your return, and look at a different pump for you loop.

You really don't need a higher speed pump (like the Iwaki) for the CL.

Additionally, you are going to be hard pressed to find something much better than an md-40 to give you that much flow at 7' or so.

You may want to consider a Sequence Snapper or Dart, as their motors run at 1700 rpm, and you will save some wattage there.

I use an Iwaki MDH-401 w/ a 1/6hp Baldor motor myself.

Pete

[spleify]

Thanks for you're input wife.
Any other thoughts?

[mg426]

Try using the Head loss caculator on the homepage. Find yourself a pump that will give you Around 180 to 300 gallons/hr 3 to 5 times tank volume @ 5.5 feet of head.

[RedEDGE2k1]

Use a small return pump, so you have more reaction time to grab the mop when your external overflow fails.

[spleify]

Originally posted by RedEDGE2k1
Use a small return pump, so you have more reaction time to grab the mop when your external overflow fails.

Explain yourself please.

[RedEDGE2k1]

External overflows will (always) fail. It might be a week, it might be a year, but eventually the siphon will break and your return pump will continue pumping water from the sump up to the tank, which will then overflow the tank and end up on the floor.

If you live on an upper level floor, this water will seep through and end up on the bottom-most floor of your building. If you live in an apartment building or the like, you'll be paying for a new ceiling for everyone below you, as well as a new floor for yourself.

Eventually. I promise.

[sjm817]

Red, you are off in a couple of ways

For one, the OP is not talking about a siphon overflow. Its an external overflow.

Second, no, a good siphon overflow will not (always) fail. There is no reason it should. It will run indefinitely without losing siphon. There are many people who have been running them 6 - 7 years without a failure.

[mg426]

4 yrs with my siphon overflow. Never had a problem.

[Lost in Tanks]

i would suggest an Eheim 1260 for your return pump. i don't think you can find a quieter or more reliable pump out there..