AZOO Anti-Ammonia Rock 500g for Freshwater Aquariums Chemical Filter Material

2 Natural environmentally-friendly mineral, composed of various kinds of zeolites. 2 Rapidly absorbs ammonium and nitrite ions, preventing aquatic life from being poisoned by bad water conditions. 2 By helping purify water, facilitates a more stable pH value between 6.5-7.5, reduces frequency of water-changes, increases the stocking density potential and the survival rate of fish. 2 Removes unpleasant odor, chemicals and harmful substances in the water.