There are several different types of microscopic organisms in our aquariums that can cause severe damage when present in large numbers. Organisms like dinoflagellates, cyanobacteria, and Cryptocaryon (marine ich) are present in most systems, and when conditions favor their presence, they can quickly get out of control. In any situation, we’ve found that nutrient control is key to outbreak prevention. By removing the substances that fuel the growth of these organisms, they’re ability to explode into an uncontrollable threat is limited. That is why water changes are just so important for long term success. Not only do you remove the nutrients that fuel the growth of these organisms, but you also remove the organisms themselves. The use of activated carbon and GFO will also help combat the nutrient problem, but those are only effective if you are continually swapping out exhausted media for fresh media.