I lucked out! my mom has a whole pile of nylon. And it's aluminum so it won't rust anyway. However, I'm changing it because I don't want him getting scratched.
U can get plastic covers and cut them to fit tight from all glass aquariums that attach to the hoods. I use these to keep fiddler crabs in on a 55 gal tank works better and nothing to worry about> i have the same on my 150 and my 220 gal tanks just remove enough that the filters fit and water can flow out.
Mine was doing the same thing.. so I cut egg crate out in the shape of the filter outlet and stacked 3lb weights on it. Well he moved the weights and eggcrate and slid out of the filter, I found him across the room dried out
It'll work for now.. but when he is bigger I don't think it will.. mine was 16"