This package includes the Nu-Clear Canister Filter Replacement Cartridge, 25 Micron, for the Nu-Clear Canister Filter Model 533 along with 1.5 lbs of Inland Seas Premium Pelletized Activated Carbon (it fits in the middle of the cartridge), a Nu-Clear Canister Filter Replacement O-Ring and Inland Seas Super Lube Silicone Lube, 1cc.

This package can also be used for the The Nu-Clear Canister Filter Model 530. The Model 530 does not come from the factory with carbon, but you may want to use carbon with it.

Carbon should be replaced in aquariums every one to two months. O-rings should be replaced once a year. Every time the 25 Micron Nu-Clear Canister Filter is cleaned, when putting the lid of the Filter back on you should lubricate the O-Ring with Inland Seas Super Lube Silicone Lube, 1cc.

Cartridge dimensions: 8.5" wide and 8 3/8" tall. Center hole is 4" wide.