Is the pump too powerful? I have no hands on experience with a sump but have read several threads on gurgling and ways to keep it quiet. Noise is a big issue with me, and if you use a less powerful pump the gurgling noise will be reduce. One person said go to your bathroom sink with bucket of water dump it fast you will hear the gurgling noise, then slow it down a lot the noise is almost nothing. There was one post on FMAS around November. I think it had links to one big thread on gurgling. I will try to find it, there several mods that people says helps.