Reef Bufferâ„¢ is intended primarily for use in a reef system where the maintenance of a pH of 8.3 is often difficult. When used as directed Reef Bufferâ„¢ will raise the pH of your reef system to 8.3 without fear of accidentally overshooting the pH to a dangerous level. Reef Bufferâ„¢ will also raise carbonate alkalinity. Reef Bufferâ„¢ is a blended product and is not just sodium carbonate. Reef Builderâ„¢ should be used to raise alkalinity when pH is not a problem. Use Seachemâ€™s MultiTest: Marine pH & Alkalinityâ„¢ to check pH and total alkalinity.