I put a new mono in my 4"x8" tank with a 16" rtc. The cat kept chasing and biting his tail shredding it. He found a space to jump into the filter over flow and got sucked up to the 1 1/4" suction pipe. Don't have to worry about the ray anymore. One thing for the ray he poked the rtc on his nose. Didn't seem to hurt the rtc, but left a red poke mark for a while.