This clear acrylic cover has been designed to fit over the rear filter compartment of the Fluval Flex aquarium.
It helps prevent fish from jumping into or out of the rear filter chamber while allowing the aquarium to be used with the original Fluval lid.
The cover simply sits in place and can be removed in seconds for routine maintenance.
The acrylic shown in some photos appears blue because it is covered with a protective film to prevent scratches during manufacture and shipping. Once the film is removed, the cover is completely clear.