Chemical Filtration: Supercharged with Zeolite crystals, these filter media cartridges absorb ammonia in a fast and timely manner. Thus, removing ammonia from your tank, and maintaining a stable pH level. Top-Quality Zeolite: These Activated Carbon Cartridges come together in a 2 Pack. For best results, replace cartridges every 2 to 4 weeks. They�re lightweight and disposable.

REPLACEMENT FILTER MEDIA: These Zeolite Crystal Cartridges are made to fit the lift tubes of Undergravel “E” filters, serving as a replacement for when it’s time to cycle out aquarium filter media. CHEMICAL FILTRATION: Supercharged with Zeolite crystals, these filter media cartridges absorb ammonia in a fast and timely manner. Thus, removing ammonia from your tank, and maintaining a stable pH level. TOP-QUALITY ZEOLITE: These Activated Carbon Cartridges come together in a 2 Pack. For best results, replace cartridges every 2 to 4 weeks. They’re lightweight and disposable. OLD SCHOOL: There has been a burst of growth, development, and ingenuity within the aquatic industry, and although we are a part of this as well, we still provide replacement media for undergravel aquarium setups. SHOP PENN-PLAX FOR ALL YOUR PET’S NEEDS: PENN-PLAX is a manufacturer and distributor of top quality pet supplies, who specialize in creating excellent pet products for animals, both great and small.