I use crock pots when I use dry ice. It works great. I put a small crock pot inside a pumpkin and put the dry ice in there too. It works great, but it is a lot of maintenance FYI.If you only need a small scale effect, say for something indoors, You can put water in a crock pot ( a slow cooking pot) set it on high which will keep the water warm enough so it will not freeze around the dry ice. If you put dry ice in a bucket of water alone, then the dry ice will freeze a layer of water around itself and stop until the pressure builds up on the ice and it pops open again, with some force I might add. Remember this is for a small effect like a chauldron or something simular, it will not fog the room up.