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. 100 mL treats 400 gallons.