Ista Rectangular Bio-Sponge Aquarium Filter (Large) Gravel Cleaners & Brushes the rear sump can be

the rear sump can be converted into a fully operational stand-alone in-cabinet sump arrangement for additional filtration capacity and equipment space

and tank walls

avoid excessive tumbling that grinds the pellets

replacing a missing bracket

Ista Rectangular Bio-Sponge Aquarium Filter (Large) Gravel Cleaners & Brushes the rear sump can beIsta Rectangular Bio Sponge Aquarium Filter (Large) High Capacity Air Driven Filtration with the Ista I 149 The Ista Rectangular Bio Sponge Aquarium Filter (Large) provides increased sponge capacity for aquariums requiring dependable mechanical and biological filtration without the strong intake of a motor driven internal filter. Its tall rectangular foam block captures suspended debris while providing extensive surface area for beneficial bacterial