The crayfish and minnows all come from a spring fed pond near my house. Typically i have enough on hand in extra tanks for both my fishing needs and for all feeding purposes. Normally i house them for about 2 weeks before i will feed my fish any of them. Gives them a bit of time to cleanse anything from them they may have picked up in the wild. I am pretty careful about that sort of thing, and it has kept my feeding expenses down to a can of flakes and pellets every few months just to feed the minnows and crayfish