Cloudy, discolored water is caused by overfeeding, biological blooms, gravel dust and other suspended particles that are too fine to be removed by mechanical filtration and stay in the water column. Fritz Clarifier rapidly clears water by pulling together (flocculating) fine particles, allowing them to be removed by the filter or settle to the bottom, leaving your aquarium crystal clear. Fritz Clarifier will not affect bio-filtration, pH or other important water parameters like other brands. Safe and effective for use in freshwater, saltwater, reef aquariums and ponds. 100% phosphate free; safe for all fish, plants and invertebrates; will not contribute to future cloudy water problems. Quickly clears cloudy water Clumps together suspended particles that affect clarity Improves filter efficiency For fresh and saltwater systems, plant and reef safe Phosphate-free Made in the USA Directions & Dosage Use 1 tsp (5 ml) per 10 U.S. gallons (38 L). Water will clear rapidly. Repeat as needed, allowing 6 hours between doses.