Great information everyone. Thanks so much!

Bill I really like your idea of a "paint roller pan" shape to allow draining and concentrating the fish on one end for easy seining.

To take it one step further, how about a small cove bulging outside of the rectangular outline -- just large enough to accommodate wooden pallets for spawning. The idea is that this would keep the pallets outside of the seining area and out of the way. Here's a crude illustration:



I realize that some fish would stay around the pallets and be un-seinable, but I should be able to get the majority, right? Any thoughts on why this would or wouldn't be a good idea?