Plumbing for drain and return

[Aquavaj]

My new tank has a center overflow with 5 predrilled holes. (2) 3/4" and (1) 1.5" inside the overflow and (2) 3/4"on each end of the eurobrace. I know the 1.5" is intended for the drain but I'm worried a single drain of that size might be noisy and I'll feel a lot better if I had an emergency drain too.

So I'm thinking of swapping the two, the 1.5" becomes the return and the two 3/4" becomes a herbie style drain. The question is, can a single 3/4" drain handle the flow for a 180g or am I stuck with a single drain setup?

 

[Jimbo662]

The 1 1/2" would be your main drain while the other two are your emergency drains. You'd want to put a gate valve on the main drain to adjust the flow and mitigate the noisy drain.

 

[Sod Buster]

5 hole is a "be an animal" setup.
Two 3/4" returns
One 3/4 full siphon
The 1.5 handles some
One 3/4" emergency plumbed fo splash into the sump.

 

[Aquavaj]

That means I'll have to use the (2) 3/4" on the eurobrace for returns right? I would prefer not to (asthetic reasons) but I guess I can if that's what it comes down to.

 

[Sod Buster]

Sounds like it. Give us a couple good pictures to study if you can. That will help with ideas.