Raising minnows and shiners for bait?

[Lard Almighty]

Not saying that you can't do it, but it will probably be a hassle. Thirty seven gallons may seem big, but it really isn't. You'll have to keep the tank well filtered and aerated at all times to keep the minnows alive, not to mention fairly regular cleanings (once every few weeks or so). With a tank that size you will probably only be able to keep 1.5, maybe 2 dozen in the tank at once before overcrowding stresses them out too much. If your plan is just to hold the leftovers for a couple of days to use for your next fishing trip, then it might be worth it. But when you consider the costs to keep the tank running (electricity, filter material, water treatment chemicals, fish food, etc.), keeping the minnows for any extended period probably isn't cost effective, and it will be better to spend that money on fresh minnows from the bait store as you go.