Review on 🐠 RONYOUNG Aquarium Divider Tray with Sucker Plastic Grid & Light Diffuser - Fish Tank Filter and Bottom Isolation (Clear) by Ashley Jones

I have tried a thinner separator and my fish kept moving it and squeezing the tip. This one is strong enough that my fish can't do that to it. The suction cups hold up well and the rigidity keeps my fish from moving them. It was used in a 55 gallon tank and required 3 rods, didn't need to be trimmed but the fish are large so a small gap at the top and bottom doesn't matter. If you have small fish, you may need to use all four pieces and trim them to fit together nicely. Or just add more gravel to the bottom so you don't have to cut.