- The sponge filter provides biological filtration, in addition, the air injection chamber produces fine bubbles that increase oxygen solubility. - Creates crystal-clear water, ideal for small aquariums. - Easy to maintain and convenient. - Applicable to different filtration systems as a pre-filter. - Uses high-level eco-friendly sponge as a filter, and uses an air pump - to ensure effective nitrifying bacteria culture, achieving stable clean and good water quality, and effective oxygen filtration and water quality.