My pump has started to make a whistling noise, I don't know if the pump is starting to fail or if it is another problem. Also, the pump seems to kick in every few minutes on my 155 gallon tank. With my sump I have about 200 gallons. The sensor is in my sump, I am wondering if I have it set wrong but I don't see how as it is pretty much keeping my tank at a constant water level. So my question is if all things are set up correctly should your pump kick in every few minutes?