He called it a green color. Probably indicating an algae bloom, which carbon won't do too much to help if it is exhausted. Carbon isn't meant to be the primary means of bio-filtration in most cases, and shouldn't be.RadleyMiller;608435;608435 said:WyldFya, it sounds more like a white nitrobacter bloom. If you remove the carbon, it will take the tank longer to cycle becasue you have bacteria on the carbon. What until the tank it totally cycled.