Whether you’re moving an aquarium or just performing routine maintenance activities, activated carbon can really save your butt. The carbon can remove harmful chemicals and polish the water, giving you the cleanest water imaginable for your fish and corals. During times of aquarium distress, such as when a fish dies or when an anemone wanders into a powerhead, the carbon is especially useful. It can help remove dissolved organic material that could eventually break down into ammonia or nitrite. In terms of water clarity, activated carbon can also remove compounds that can cause a yellowish tinge to the water, making that water extra clear.