This filter ball is made of for durable and practical use. It has the best effect on fish tank water. It can be used in sea water tank, water tank, aqua-plant tank. And its strong filterability can stable water quality and reduce fish died. Feature - ColorAssorted Color - Material: . - Size: Approx. 1.5 x 1.5 x 1.5cm. - Help improve water quality, and provide suitable environment for organisms. - Strong filterability. It can be used repeatedly after cleaning. - Suitable for sea water tank, water tank, aqua-plant tank. - Increases the ability to transport and increases oxygen content in water. - Great fish tank and aquarium filter ball and give the fish environment. - Warm Tip: Dear buyer, due to lighting effect, monitor’s brightness, manual measurement, etc., there could be some slight differences in the color and size between the photo and the actual item. Sincerely hope that you can understand! Thank you! Package list: 1 x set of 400-500g filter material