ISTA External All In One FilterExternal Filter which can either be hanged on the aquarium or stand beside it. Comes equipped with high quality filter media including bio sponge, ceramic filter material and activated carbon cotton board. Easy to operate, to clean, and to change the filter media. The ISTA External Filter automatically exhausts airs to prevent pump difficulties and has four security locks to ensure no water leakage. Low vibration and ultra quiet operation. ISTA