Fine porous sponge maximizes colonization of beneficial bacteria to help keep water crystal-clear. Simply set-up by attaching your air pump (not included) to the Nano-Sponge filter, and suction it to the side of your tank with the two included suction cups. The two sponges are designed to house beneficial bacteria without allowing baby fish, shrimp, or other underwater creatures get sucked in. Safe for freshwater and saltwater tanks.
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