Overflow box Gph

[Gilbert]

how can i tell the GPH rating on my overflow box? i dont believe its labeled, so is there anyother way to find out or all they all the same?

[ErikH]

If it's a standard box, something like 1 1/2" the biggest return I would use is a mag7. That's what I have on mine, I can still pour a couple of gallons into the display and it is just fast enough to handle it without overflowing.

Remember, your return pump can be much slower. You just cannot exceed the rating.

I am assuming it is a single overflow?.?

[Mr Cob]

They vary depending on size and bulkhead size plus drain size.

I tried to find some info but this is all I could find...read through it, the second post has some useful info:

http://www.nano-reef.com/forums/lofiversion/index.php/t37221.html

[Mr Cob]

FYI: I have a dual overflow that pulls about 1500gph and I use a Mag 18 to return the water.

[coraline79]

had a single eshopps and it was at 700gph

[Mr Cob]

I also have a single eshopps but its only 300 GPH.

[aggman]

to answer your question...you can test the flow of your overflow by measuring how fast it fills a gallon pitcher. assuming you have a way of doing that...if it fills a gallon in one minute then you got 60gph and so on.

~alex