Refugium

I am setting up a refugium. And need ideas a pump GPH and overflow box . The top of the tank is @ 5 feet off of the floor. It is 40 Gallons.

 

Is it Glass? If so you could drill it for a drain.

 

it is glass. but it has been set up for about 3 months. I really don't want to empty it to drill it.

 

Just use a hang on back overflow rated for around 600gph, and use a mag 9 pump and you should be fine.