WMU7071 Aquarium Wet Fish Koi Pond Filter Bio Balls 16mm/26mm 20pcs

Package Includes: 20 piecesMaterial:Plastic Spongia Color:Black Size S:16mm Size M:26mm 1.The bio-sponge inside provide more surface area for growth of beneficial Bio-Spira bacteria 2.BIO-Balls do not require replacement unless damaged or destroyed 3.In the event of excessive buildup, you may gently rinse with water from an established aquarium, if desired

Notes: Due to different production batch, inner sponge is filled in random color, it might be yellow, green, black or other colors. It does not influence normal using, they are all made of the same materiral. So please know about this point before you buy it. Thank you for your understanding and support.