JMB
Aquarium Advice Apprentice
Here's a question I've never seen on this site. I have a 65 gallon tank with an overflow that drains down to a sump filter. The return has a mag pump rated at 750 gallons per hour. My question is this, there is usually a gurgling sound coming from inside the overflow. It sounds much like a bath tub as the water runs out, I imagine it is because the flow going into the overflow is not fast enough to build up the water level inside the overflow, it is simply constantly flowing through the hole, into the sump and being returned. Is this normal or should there be more water building up inside the overflow than is going right down the drain? I do have filters inside the overflow.