I haven't tried it, but, the easy way to get around that would be to put a dish of ff that will kind of sit on the top of the dog bowl, then fill the dog bowl. Kind of like a double boiler, the dog bowl heats the water, the water heats the ff.Winter is a pain. I carried 17 birds through the winter last year. They ate FF almost 100% of the time (in addition to their sprouts). This year, I am carrying 30 birds, so may do a combination of FF and pellets. We'll see how it goes. I may also change up my waterer, make a cookie tinor stock pot heater for the water (horizontal nipples). This will free up the heated dog bowl for the FF. Any one have experience using heated dog bowl for FF? I'm concerned that it might overheat b/c there won't be any water. Less circulation.