question about return pumps for sump

[sphelps]

I talked to the Quiet One manufacturer before about a few problems with the pumps, mostly being noise and restarting issues. They stated they both result from overheating which usually is a result of lack of maintenance. Lime deposits build up fairly quickly on these pumps and cause excessive friction resulting in more heat which warps the impeller magnet. This causes excess noise and sometimes prevents the pump from restarting. They said a new impeller usually fixes the problem and it should be cleaned regularly to prevent failure. High calcium tanks are more susceptible to this problem.