We have to use strong deer netting to keep the critters out, we have no choice. Without it we have the neighborhood Kitties trying to go fishing and there are Raccoons taking a swim and I don't what else. We only keep Paradise Fish in our small pond over the Summer, and there are lots of hiding places, but I hate to see everything constantly disturbed and I don't like to lose any of the little fish. We have to make sure the netting is really tight around the edges, or critters will get underneath the netting.