I have a 125 that couldn't move. So we used this thick black contact paper with the good side facing toward the tank. Cut to measurement first. Spouse held the other corner up tight & taped it on with clear gorilla tape. Tape goes down the whole side and blends in with the seam. Didn't have to squeegee any water out and it looks perfect. Has to be tight or you get distortion. Cheap, didn't have to move the tank, and only took about 10 minutes. Easy to change also if you get bored with the black.
Ignore the dirty glass, gotta clean it haha
