Flow rate for HOT box

[DonMorse]

Hey guys, I'm setting up my mothers tank that has been down since Hurricane Charley left us with no power a few years ago. She has a generic overflow box with 1 1/4" pvc plumbing. single bulkhead. What is the flowrate for that diameter pipe? I'm trying to find a pump (she lost hers) and am looking at going with a Quiet One. I want as slow a flow as possable as this is going to a 'fuge. any help?

[leveldrummer]

i believe a pump of around 600 gph is usually what those overflow boxes can handle, not sure though, can you track down the brand of over flow? try to get the actual specs on the one you have?

[DonMorse]

The box has no markings on it. I measured the bulkhead, figuring the box size doesn't matter just how much can flow out. As for the 600gph pump, I'm planning on trying to keep the turnover low (it's not the only source of flow) if I run a 300gph pump will I risk breaking siphon? Anyone have any experience with short changing the flowrate into the overflow?

[tperk9784]

Originally Posted by DonMorse

The box has no markings on it. I measured the bulkhead, figuring the box size doesn't matter just how much can flow out. As for the 600gph pump, I'm planning on trying to keep the turnover low (it's not the only source of flow) if I run a 300gph pump will I risk breaking siphon? Anyone have any experience with short changing the flowrate into the overflow?

The overflow shouldn't care what amount of flow you put into it as long as it's under it's max capacity.

Hopefully there is a small section inside the overflow that will stay filled with water even if the flow stops to maintain the siphon in the U-tube. If it doesn't you should mod it or toss it and buy one that does.

[luvmylo]

Originally Posted by tperk9784

The overflow shouldn't care what amount of flow you put into it as long as it's under it's max capacity.

Hopefully there is a small section inside the overflow that will stay filled with water even if the flow stops to maintain the siphon in the U-tube. If it doesn't you should mod it or toss it and buy one that does.

agreed, just don't go with anything too big and you should be good to go. I'm actually thinkin bout downsizing my pump. 500 gph now to around 300 or so. reason being is I don't think all the water in the sump is being skimmed.