Plumbing in a 120. What should I do

[MRCORAL]

I setting up a 120 with 2 overflows. What do you think on the plumbing for it. Should I bring in the water to the sump with s pipes ot t it before the sump? Same thing on the return?

[Avi]

I have a 120 with two overflows myself. I've been happy with the configuration that I have and though I'm always looking for ways to improve things, I find no need to change it. All it is, is an "accordion" type hose coming down from each of the overflows to one side of my sump/refugium. The return-pump is on the other side of the sump/refugium and send the water to the tank via a nylon tube "T"d off to two outlets, one hanging on each side of the back of the tank. It's simple but works well with no complicated plumbing involved.

[Konadog]

I would keep two separate drains to the sump just incase one has a problem. As far as the return goes, if you tee it you will lose velocity (pressure) but may increase flow by a little.

[MRCORAL]

You think a Mag 9 is enough?

[Black Mammoth]

I would suspect that a Mag 9 would be enough. Remember, your piping needs to be 2x the outlet. I think the Mag 9 has a 3/4in outlet. If that's the case, you need to run 1.5in piping.

[MRCORAL]

It need to ne 2x the outlet why?

[Black Mammoth]

If you do the outlet size, it will restrict the flow. If you look up the Mag drives, you'll see that's what the manufacturer recommends. I was surprised when I heard this myself, but it's true.