[Edwell]

Because of space I am installing a fuge above my 42 g hex tank.

I am pumping from by tank to the fuge (16g) and gravity drain back down to the tank. I drilled the bottom of the fuge for a bulkhead and ran 3/4" tubing from the bottom of the fuge to the bottom of a prefilter box. The prefilter box controls the level of water in my fuge.

By problem is the prefilter box drain gurgles. Besides the noise it puts bubbles into my tank. I have tried to put a sponge over the drain and adjusted flow into the fuge but still have the gurgles.

Any suggestions on how I get rid of the gurgles???