I'm looking to put in a fence line auto water this summer in one of my dry lots. I get very tired of filling up tanks. Wanting some recommendations on which I want to use. I have seen the ones with the bule balls and also some that have a plastic flap that flips down over the hole. I haven't been around either kind. Wanting something that is reliable and durable, as I use this lot for bulls often. Open to other suggestions aswell. I live in se Kansas, so it doesn't usually get extremely cold for extended periods. Thanks for your help