12 Pack Replacement Small Size Cartridges for Tetra Whisper Small Fish Tanks Filter; Refilled Filter Cartridges S Size for Aquarium Kits 3-10 GallonsBrand: ShuRex Color: White Features: Perfect replacement for Tetra Small Filter Cartridges S Size; works for 3~10 gallons small fish tank filters; Measures 4" x 2. 2" (L x W), fits many brands of Small HOB filters. Please check compatibility before purchasing. Replacement for imagitarium B C filter; Replacement Filter Media Cartridge for NuWave Betta Fish Tank In a three layer filtration design, double layer microfiber cotton can effectively absorb