How to clear aquarium water safely for all freshwater fish! WaterClarifier works to quickly clear cloudy or hazy aquarium water. This easy-to-use formula safely settles minute particles and cloudy water caused by overfeeding, gravel dust, and other particles. WaterClarifier is safe to use for all freshwater aquariums and is phosphate free. How it Works WaterClarifier works by causing small, suspended particles to quickly clump together. These larger particles are then removed during normal power filter operation or they settle to the bottom and are removed during gravel cleaning. Safe and Effective WaterClarifier is a safe and effective formula based on clarifiers used to treat drinking water. It is phosphate-free, safe to use with fish and plants, and will not affect water pH levels in your aquarium.