Two Little Fishies CDX cleans up carbon dioxide before it enters your system helping to keep your aquarium’s pH from dropping due to excess atmospheric CO2 getting into your system.

TLF CDX is a carbon dioxide absorbing system media that you just add to your PhosBan reactor and connect to the air intake of your protein skimmer.

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.