I'd remove it.. and stick with sponges. They are mainly in the removal of odor and discoloration. However, these things should not be an issue at all if enough water changes are being done. At this point it would simply be ‘if it can help, why not use it?’ There are other issues as well, carbon is not selective. It removes a lot of different chemicals whether they are good or bad. Some of these are trace elements and micronutrients. These are vital for the proper physiological function of fish, plants, and invertebrates. Carbon is an unnecessary and even harmful media that does not need to be used in the aquarium except for short-term applications such as removing medications.
Last edited by Myates; 11-04-2012 at 06:29 PM.