Hello everyone i just build a pvc overflow with 1" pvc pipe for my 90 gal tank at the moment i am using a pump that is pushing 258 gph. I read through all the PVC overflow thread to get a great understanding how to build and work one. Well here is the issue when i built the overflow i did like everyone stated and it worked fine when i tested it out in the bathtub, but when i put it in the tank a whole different story. i sucked all the air out and the water to start to siphon, but when i stop sucking for a few sec the water stop draining. when the water seem to come back up the tube that draining the water it appears to have bubble. What am i doing wrong please help!!!!!
