Return Plumbing Question

weaponsofmassdesign · Apr 22, 2012

I have a 165 gallon 72" long tank with two overflow boxes, one on each end. Each overflow box has one drain and two returns. Each of the four returns are 3/4". I'm using a Mag 18 return pump for now, and I may upgrade to a Mag 24. The return pump is on the right of my 40 gallon breeder which I've position exactly middle under the display. The drain is on the left so the drain on the right is longer than the left, so the return on the right will be shorter and the return on the left will be longer. I have to split once from the return pump and then once more for each of the two returns on each overflow. The way I see it with a tee the water will bypass one of the returns on each side of the tank. Is that correct and should I be doing something else? I would like to use PVC rather than vinyl tube and would like less horizontal pipe as possible.

Sorry if this is confusing. Hopefully it is understandable. I wanted to provide as much information as possible. I can provide more if need be.

btkrausen · Apr 22, 2012

Try a Y instead of a true T, maybe that'll help.

I didn't split mine, just ran it through one return on my 220 and it works fine. My tank came with 2 overflows, which had one return and one drain each. I used both 1 inch drains, and turned one of the returns into a third drain for safety. The one 3/4 pushes quite a bit of water, probably close to 900gph.

Just my 2 cents ;)

pgr11 · Apr 22, 2012

Not fully understanding. Can you shoot a pic of what you are trying to acomplish? or the area you are working with

weaponsofmassdesign · Apr 22, 2012

btkrausen said:
Try a Y instead of a true T, maybe that'll help.

I've tried to find a 3/4" Y but can't locally. I've found one website with ridiculous shipping. Where did you find yours?

weaponsofmassdesign · Apr 22, 2012

Here is the bottom of the overflow. One 1" drain in center and two 3/4" returns on either side. I have two overflows so this is on each side of the tank.

This is the side with the return pump and the right return is just above and slightly to the right of the return pump.

The middle where the plumbing will crossover to the left side.

The drain side of the sump with the other returns just above and to the left of the drain.

And another view for extra measure!

pgr11 · Apr 22, 2012

If all you need is a 3/4 Y any local irrigation supply store will have one. The big box stores most likely won't.

btkrausen · Apr 22, 2012

I plumbed my three drains together, three 1 inch drains into a 2 inch drain. They go into a Y, with the one outlet going to the sump as you can see below. You can see my single return of the left side of the picture.

Really, for a 165, you don't need to split your return into 4 outlets, thats quite a bit, plus, you'd have to be pushing a bunch of water to get any kind of pressure out of 4 outlets. Personally, I'd make two of them drains on each side, and one a return. You want more draining throughput than return throughput.