I needed to find either a different lid or another type of cover for the Fluval Spec 5 gallon fish tank, not because I was afraid my fish could jump out, but because our cats took an interest in drinking from and playing with the fish tank water. I was afraid this would make the cats sick, make the fish fearful or even hurt the fish, so I turned to Amazon to see what I could find. I thought about using the type of lid that was a mesh material, but could not find one the right size and I was afraid it would eventually rust. I also thought about adding something to cover the opening of the existing lid. I decided to revise my search to see if there was something made specifically to fit the cover I have and found this. Yes, it is pricey for what it is, but it looks so much better than anything I could have tried to add to the tank. You can tell it is 3D printed from close up, but it looks like it was made for the tank! It definitely serves its purpose