I hope someone here can help me. Although I do not have an aquarium set up for fish, I do use them for terrariums and I set them up for tree frogs. I found a great deal on a 30 gallon (used) "bow" aquarium. It does not have any top on it. If I am going to use it to house frogs I need it to have a secure screen top. I have searched through some pet stores and I have only seen screen tops for rectangular type aquariums. Is this a lost cause...do they make screen tops for "bow" aquariums.