Reef Endurance Bulk Soda Ash 25lbPharmaceutical Grade Soda Ash Aquarium Supplement Reef Endurance Soda Ash is a Pharmaceutical based reef aquarium supplement that mixes crystal clear with no unwanted impurities. In reef aquaria, maintaining alkalinity within a range of 8. 0 12. 0dKH will enable corals and other reef building invertebrates to grow properly. For best results, use in conjunction with Reef Endurance Calcium Carbonate as a two part solution. Replenish and maintain