I'm sure there ton's, but here's a few I got.
If your minner slits out of your hand and hit the boat floor...then flops around a bit, be sure to put him back and get another, because all his wiggle is gone. Second is to be sure to add fresh lake water to your minners slowly, so they become use to the lake water temp a little at a time. It might take a 10 minutes or so, but make a big difference.