or get a dorm fridge gut it put the cooling coils in the sump n u have a diy chiller. or get a dorm fridge a lot of tubing coil it up put it in the fridge get a small pump to pump water from sump through the coiled tubing cooling it before it goes back into the sump.

just ideas I have when the little mouse starts turning his wheel. I have not tried these ideas so if u try them try them at ur own risk I am not responsible for the bad out comes but if it works then it was my idea.