If everyone has Kayaks then there is not too many options other than what people have suggested. Stringers/Wire baskets WILL kill the fish, fast. I am currently part of a smallboat/smaller waters tournament and almost everyone uses 10+ gallon coolers with Aerators that you can get at most fishing stores. They have them at Dick's and Bass pro and they run about 25$ and work just fine. If you guys mostly have kayaks tho, this would be pretty hard to fit. Total inches is not a bad idea. Another option is to do 2 people in each canoe and they are witness to one another's weights/fish...