How to set up a Protein Skimmer?

Hello guys!

So i was given a external protein skimmer for my new setup.
(With no instructions or part number) So i am unsure on how to hook it up correctly.

i know the basics like where to hook up the ingoing water pump and where to run the outgoing plumbing Etc.

BUT.. there is a little what looks to be a drain right below there very top chamber of the Protein skimmer.

What is this for?

And how do i hook it up?

 

A pic or a brand name might help. Is the drain on the top chamber a drain valve for the collection cup?

 

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Probably, get some tubing to hook it up to a seperate collection container ie. a piece of tupperware or similar with a hole drilled in it

 

I believe it is a drain. I will try to get a picture up soon. Its the very top chamber. There is only 4 plumbable spots on my skimmer two i know are for ingoing and outgoing water one i know is for the air. So the fourth has to be a drain. Just how do you plumb this drain?

 

should prob just have a cap, take it off, push tube over it and drain to something.