Bean animal overflow help please. I have a 151 gallon, this is what came with the tank, I’m unsure if manufacturer or if store made them. Three drain lines in overflow. The emergency is cut and dry. The other two are exactly the same with 3 holes drilled in the top and maybe 1/8” difference in height. I am by no means an expert, but doesn’t seem right to me. Can anyone help me understand this better?