Works faster, lasts longer. Premium activated carbon is up to three times more effective than competitor's brands. Laboratory tested and proven more effective at removing foul odors, unsightly discoloration, and harmful dissolved organic waste. Ideal for all your filtration needs. Keeps aquarium water healthy and sparking long after other carbons quit. And, more pure activated carbon in every jar. As much as 60% of "prewashed" carbon weight is water, not carbon. Unlike other carbons, Black Diamond contains less than 2% moisture. More carbon, better value. Phosphate free. Convenient, resealable container.