Aquarium pH Buffer replenishes the carbonate and bicarbonate required to maintain or increase the alkalinity of captive marine systems. Alkalinity (carbonate hardness) in captive marine systems constantly decreases as biological processes remove carbonate, and produce acids that neutralize carbonate. Proper alkalinity should be maintained around 2.5-2.9 me (7-8 dKH) for marine fish tanks and 3.2-3.6 me (9-10 dKH) for reef tanks.

Sometimes aquariums in closed offices and homes maintain a low pH due to the accumulation of carbon dioxide in the air. This excess CO2 dissolves into the aquarium water and depresses the average pH. The Two Little Fishies CDX Carbon Dioxide Adsorption Media helps maintain and elevate aquarium pH by removing CO2 (carbon dioxide) introduced through a protein skimmer. Simply pour the CDX into a tall columnar reactor such as the Two Little Fishies PhosBan Reactor and connect the CDX-filled reactor to your protein skimmer's air intake hose. You can use the Two Little Fishies CDX Adaptor or a similar barbed, reducing fitting to connect the air intake for the protein skimmer to the outflow pipe of the reactor.