just curious. has anybody ever used hot water run through a series of plumbing in your sump or other stage of filtration?? my father tried this concept but it was not up and running very long. i know that there was a series of pipes with valves that would direct hot water thru another series of pipes inside of his sumps for a certain period of time and than the valves would close and the system would stop running. anybody interested or with any knowledge of a system as such please post. my father's sumps were around 8 ft long and 4 ft wide in his last hatcherey. could this be pulled of with a smaller volume of water and is it cost effective or efficient?? thanks