How much gph can my overflow handle?

[crimzy]

My tank is drilled with one overflow box, containing two 1 1/2" drains in it. I am considering replacing the return pump and am wondering how much flow I can have without it backing up. Anyone know?

 

[trippkid]

About 1500gph for each hole. So, 3000gph is what can come down.

 

[crimzy]

Thx.

 

[trippkid]

Sure no problem, I was 100gal/hr off though, sorry for that. It is roughly 1600gph, most likely though it will be closer to the 1500 per hole. So somewhere between 3200 and 3000 I'd say. Sorry for the mistake.
Matt

 

[saltn00b]

why are you considering replacing the return pump? usually you dont want massive flow through a sump, but the majority of the flow in the system should be from powerheads or a closed loop system.

 

[crimzy]

Originally Posted by saltn00b
why are you considering replacing the return pump? usually you dont want massive flow through a sump, but the majority of the flow in the system should be from powerheads or a closed loop system.
My return is old and sometimes it does not want to start back up after water changes. I have to mess with it and constantly take it apart to clean and put it back together just to get it working. And, I'm sure the gph has diminished over the last few years.

 

[saltn00b]

ok, what size tank do you have? sump? is the sump a fuge? what GPH is the pump you are replacing?

 

[crimzy]

Originally Posted by saltn00b
ok, what size tank do you have? sump? is the sump a fuge? what GPH is the pump you are replacing?
The tank is a 225 with a 50 gallon sump/fuge. The current pump is listed at 1200 gph but I know it's pushing much less water than that. I also have some ph in the display.

 

[saltn00b]

yea you are probably going to want to have an actual GPH of about 1500 from your return.