This Maintenance Kit includes three types of filter media for your AquaClear 110/500 Power Filter. Used together, they deliver highly effective 3-stage filtration to create a happy and healthy aquatic environment. Bio-Max Insert (2 x 13.76 oz): This ceramic media provides an optimal environment for the colonization and growth of beneficial bacteria, which is essential for effective biological filtration and water purification. Bio-Max media features a complex bio-ring pore structure which allows toxin-reducing bacteria to thrive. By reducing harmful nitrite and ammonia, Bio-Max increases the efficiency of your biological filtration by up to 30%. Bio-Max media comes in a mesh bag insert for convenient installation. Suitable for both freshwater and saltwater applications. Carbon Inserts (2 x 9.17 oz): This premium activated carbon improves overall water quality in freshwater and saltwater aquariums. Its exceptional adsorption properties effectively eliminate discoloration, odors, and impurities. Foam Filter Insert (x 1): This mechanical filter media effectively removes debris and particulate matter from your aquarium water, while preventing waste particles from prematurely clogging the other media in your filter. Primarily a mechanical media, the porous foam structure also provides powerful biological filtration as it is an ideal site for the growth of beneficial bacteria. Suitable for both freshwater and saltwater applications. Maintenance: For optimal results, replace Foam insert every 2 months, Carbon insert every month, and Bio-Max every 2 - 3 months. Never replace all filter inserts simultaneously to ensure the constant presence of beneficial bacteria. Rinse all insert thoroughly before use.