Is my sump assumption correct?

[MattP725]

I am setting up my first sump... I am wondering... if I make the inlets in the glass about 3/4 of the way to the top (I will be drilling the bulkheads and not just running in pipe)... the sump shouldn't fill any higher than those bulkheads right? Even if lets say the pump dies off for some reason (not including back siphoning) when the water level reaches the top of the inlet bulkhead on the sump it shouldn't raise above that because of gravity right?

 

[Dr.Nate]

To prevent back siphoning and overflowing the sump, on mine I had to drill a small hole on the return pipe to the main about 1" below the water level on the main.....so that when it back siphons, it only does so until the main water level gets to that hole and then it starts sucking air and breaks the siphon. I'm not positive that's what your question was, but maybe it helps?

 

[MattP725]

No that wasn't the question. The question was on the drain when I drilled the drain side of the sump (Most people just have the drain go through the opening on the top) will the water in the sump stop at the top of the bulkhead if the pump were to stop working. Forget anything about siphoning. Basically if you drilled the side of your sump and ran a drain down to it. If there was no return would the sump overflow or would it stop when the drain bulkhead (on the sump so you could call it the inlet on the sump) was fully submerged.

 

[Brenden]

The water will drain from the tank until it reaches the bottom of the tank bulkhead regardless of the bulkhead in the sump.