Description: Feature: Perfect for 0.5-5 Gallon aquariums. Simple to run off airline tubing and a tiny air pump. Light in weight,compact and portable, convenient to replace and store. Sponges can provide physical filtration, they can remove harmful substance in water. Specifications: Main material: sponge Color: as pictures shown Size: about 8 x 7 x 4 cm/ 3.14 x 2.75 x 1.57 inches Package includes: 2 xaquarium filter sponges
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