Clear-Carb combines the benefits of Carbon and Clearmax for fresh and saltwater aquariums. It eliminates odors, discolorations and impurities, while controlling phosphate, nitrite and nitrate to produce crystal clear water. 2-in-1 premium activated carbon with Clearmax chemical filter media Highly adsorbent – removes odors, discolorations and toxins Helps promote healthy, crystal clear water Reduces phosphate, nitrite and nitrate for a healthier aquarium Improves fish health Reduces aquarium maintenance For best results, replace every 4 weeks For use in freshwater and saltwater aquariums