SeaChem Reef Plus ? is a full spectrum reef supplement containing trace elements, vitamins, and amino acids demonstrated to have a positive impact on the growth of corals and other desirable reef creatures. Reef Plus? is formulated to provide nutrients available from natural tropical reef waters. Contains vitamin B12, vitamin C, thiamine, inositol, choline, iodide, and other essential constituents at pH 8.3. Reef Plus? is nitrate/phosphate free. It may be used as a food supplement. It complements Reef Complete? and Reef Calcium?. It is a concentrated product: each 2 L treats 32,000 L (8,000 gallons).