Mesh size should be okay providing fish are greater than 3". Only problem might be with fish eating birds such as herron etc. Greenies would not need "as much space as possible", and "some natural bottom to hang out on". Those are humanistic determined features not needed by fish as long as water quality is good. The larger area will make it more difficult to feed train the fish. Fish feed train most successfully (highest % going on feed) when they are in crowded conditions. NOTE - Try to keep all greenies to be of similar size in the net area. If some are 2.5X longer than others smallest ones will be fish food.
