The Nu-Clear Model 1522 Extension Kit doubles the height of the Nu-Clear filters, allowing the use of two cartridges and twice the amount of carbon. The extension kit for the Inland Seas Nu-Clear Model 522 Canister Filter, 100 Micron Cartridge & Carbon Filter includes the extension housing, 18 sq. ft. 100 micron poly-screen cartridge, and a 1.5 lb bag of premium Inland Seas Marine and Reef activated carbon. It expands the capability of the Model 522 Canister Filter so it can handle freshwater and saltwater fish-only tanks up to 180 gallons and ponds up to 600 gallons.
All extension kits include the body extensions, stainless steel band clamp and 1″ mpt port plug. Extensions kits include a plug for the redundant inlet on the bottom filter. It is not recommended to mix different types of cartridges or media (i.e. Do not use a Model 522 with Extension Kit 1547, only use the Model 522 with the 1522 Extension Kit).