Help Please

[Tommy3492]

So I have a 90 gallon scaquarium.

There is a middle overflow box with 3 holes.. 2 drains and the one in the middle is return.

it came with a durso pipe, and looks like another pipe for a herbie..

I would like to use the durso pipe, and put in another pipe for the herbie...

Does this work? Can anyone explain my best plumbing options with these 3 holes?

Pictures would be awesome, I can learn much better visually.

 

[Dkuhlmann]

It makes no sense to me to have a return in the middle of two drain pipes in an overflow box. I'm guessing it's an emergency drain. Can you post a picture to give a better understanding of what you have?

 

[Bogue Chitto]

That's what I was thinking Dk.

 

[Tommy3492]

Pictures

Pictures

Yeah I thought it was weird when I saw it too...

Here are some pictures.