Grubb, couldn't you just seine or catch the bg and put them in the smallest pond and then as you catch them add 'em back in the pond you want? Or, what about an aerated stock tank for storage or a floating basket. We have 2 of the floating baskets made from 4" pvc glued into a square and attached to a 2x2 wooden frame with plastic netting stapled to it. We used to start our bass fingerlings in one and cats in the other. Thats all the help I can offer, I hope it helps.