It’s a shame they’re so fragile. Stinks when you leave the baitshop with a dozen but only have 8 by the time you get to the lake because sloshing around in the minnow bag in the backseat was too much for them.
I can keep suckers or rainbows alive for a couple weeks in my garage in the winter. I just do 50% water changes a couple times a week with tap water that’s sat out for a couple days to release the chlorine. Put a $10 aquarium aerator in an insulated bucket and you’re good to go. I keep water ice cold, even to the point of having the surface ice up.