Return pump

[Ardee]

i am a new reefer. I have just got a 120 tank. Need help with plumbing aspect. I got a glass cages tank. The overflow box had 2 holes for sump. One is 1.5 inches and one is 1 inch. My question is where does the return pump go! Does it come back in the smaller hole or is both of this for draining to the sump? If so, where do I put return pump? Thanks for all help!!'

 

[TaylorPilot]

You can do it either way. Look up "Herbie overflow". Typically, the bigger hole is for your drain, and the smaller is your return. But people had devised a way of running both as the drain. The benefit is that it is completely silent, doesn't introduce allot of air, and gives you a backup in case one of the drains clogs. The only down side is that your return now has to come up over the back of the tank. This requires you set the tank off the wall a little. Although I would do that anyway, because you never know when you may have to do some inventive wire or hose routing. Welcome to R2R!

 

[mfinn]

i am a new reefer. I have just got a 120 tank. Need help with plumbing aspect. I got a glass cages tank. The overflow box had 2 holes for sump. One is 1.5 inches and one is 1 inch. My question is where does the return pump go! Does it come back in the smaller hole or is both of this for draining to the sump? If so, where do I put return pump? Thanks for all help!!'

I like the idea of having 2 drain holes.
IMO it's just a safety thing.
With your tank if you decided to use both holes in the overflow box as drains, as Taylor said the return line would have to go up over the top, which isn't a bad thing.
If you decide you want to use one of the holes in the overflow box as the return line, use the smaller one for the return and the larger one for the drain.