OK so I have a 275 gallon oil tank I wanted to recycle into a fish tank. Picture below is what the tank looks like. I want to cut the top off where its rounded and use that as a lid for the tank. Then I want to cut a window running about 4 and a half feet by about 2 and a half feet and put a plexiglass sheet in for a window. Note this is still being thought out but any tips or ideas would be great. I work for a powder coating company so i would burn off and then blast the whole tank to remove chemicals and the oil but what would a good coating be for the tank to keep it from rusting? Are the pet safe coatings? Is there a rubber coating I could use? How thick should the plexiglass be? Any help would be greatly appreciated. Thanks.

