Reef Endurance Bulk Sodium Bicarbonate 25lbPharmaceutical Grade Sodium Bicarbonate Aquarium Supplement for Higher pH Systems Reef Endurance Sodium Bicarbonate is a pharmaceutical based reef 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. Sodium Bicarbonate is excellent for aquariums that have a naturally high pH. Unlike soda ash,