I don’t know how much room you have but I use an old horse water tank. I have an aquarium 110v double bubbler and I have it plumbed into my well. The water comes on twice a day for a couple minutes from a cheap sprinkler timer.
The tank is covered with an overflow drain to the outside. So the combination of covering the tank, fresh air, fresh water keeps it ice free for all but the -20 days. When I see it get some ice I put a small stock tank heater in it for a short time. If it gets ice on top I scoop it out. The larger the tank helps too.
I keep 4″ shiners and fatheads in it all winter here in Montana. Fresh lively minnows are hard to get here anytime of year so I baby them critters ……