If you are keeping the tank outside, the shallow (24") would lead to winter death do to ice over unless you kept it heated somehow. It would also preclude the use of tropicals. If you have access to tadpole madtoms in your area, catch a few of those. They would definately clean up the dead fish but wouldn't heavily prey upon the FHM at the same time. You could also look into putting some lake chubsuckers in the tank as they feed on algae if you can find a wild source to catch them from. Plus, they would make a great addition to any pond's forage base if you could get them to spawn in your tank. Good luck!