Max, I have a waterer similiar to yours, only not as tall and a different brand. Mine holds 3 gallons. Never had any problem with it leaking. We greased the O ring with vaseline and (I'm thinking this is important) I only hand tighten it. I don't try to put the lid on as tight as possible and I can remove the lid with one hand. As I said, no problems with leakage at all.