I fish for crappie with medium minnows. Sometimes, the crappie bite isn’t so hot, so I end up having 2-3 dozen leftover. In the beginning, I left them in the minnow bucket with the aerator running, but it burns a lot of batteries, and plenty of fish still die. I don’t have space in my fridge. I ended up finding my old 20 gallon tank, installing the small water filter that I already have, and leaving it in my bathroom counter. I have an aerator for the tank, but I only run it when I’m taking a dump or shower. Initially, a few died, probably to the shock in water quality and temperature. Of course, I treat the water with pH down, AccuClear, and tap water treatment chemical. I also add chemicals that help regulate ammonia levels. Fish seem real happy. I feed them goldfish food, but I grab a good size pinch and crush it a bit, since the minnows are so small. I also feed them frozen blood worms that you can buy at Petco, but only every few weeks. I have a few dozen in the tank, and they seem happy. Might add a couple more dozen and see if they will breed to produce more minnows. Will take years, but fishing only runs a couple seasons for me.