50x50x4cm Small Hole Fishing Tank Filter Cotton Aquarium Biochemical Cotton Cultivation Filter Material

1. Suitable for seawater, freshwater, aquascape, size can be freely cut
2. Dense pore gap and softness is suitable for cultivating good nitrifying bacteria
3. Decompose excrement and feed residue, improve water quality, good filtration and cleaning effect, reduce fish mortality
4. Wash once a month with water, no blockage, no deformation, can be washed again and again after cleaning
5. Thickened material, strong water permeability, more thorough and detailed filtration
6. Material: cotton