ITEM NAME:Filtration Foam Aquarium Fish Tank Biochemical Filter Sponge Pad Mat 50x50c K4U3 Filtration Foam Aquarium Fish Tank Biochemical Filter Sponge Pad Mat 50x50c K4U3 Thickening Biochemical Filter Sponge, tough and durable. Size: Approx 50x50x2.5cm (L*W*H) Moderately hole, can cultivate high density nitrifying bacteria Can be used repeatedly after cleaning 100% Brand New and High Quality This Fish Tank Biochemical Filter Sponge can be used in sea water tank, fresh water tank, aqua-plant tank The size can be cut freely as you need Good shading features, can reduce the algae breeding Strong filterability, can stable water quality and reduce fish died Suggested to clean it every month Color: black Package include: 1Pcs Aquarium Filter Sponge Note:Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.