Kent Marine Nano Reef Part A & Part B 8oz. Kent Marine Nano Reef Part A & Part B is a calcium and alkalinity supplements formulated for nano reefs and smaller reef systems. Kent Marine Nano Reef Part A & Part B is an easy-to-use, 2-part liquid system which is vital for healthy coral and invertebrate growth. This product provides all the important major, minor and trace elements in their proper ratios. Kent Marine Nano Reef Part A & Part B also increases alkalinity and maintains the optimum pH level. This supplement also minimizes accidental overdose and any adverse chemical reactions in the tank water. Each 8 oz bottle treats 475 gallons of tank water. Please refer to the product guidelines for the optimum frequency of use.