Many aquariums suffer from low-pH issues. Sometimes it`s the carbon dioxide that accumulates in the air in closed buildings that won`t let the pH of your aquarium stay up. TwoLittleFishies have the solution: It`s called CDX, a Carbon Dioxide adsorption system.
Simply install CDX media in a media reactor and connect it to the air intake of your protein skimmer. The CO2-free air injected into your protein skimmer drives off the excess CO2 dissolved in the water, so the aquarium`s pH rises.
A 750 ml jar will last about 6-8 weeks on the average 50 - 100 gallon reef aquarium. You can tell when it is exhausted because it changes from white to pink.