Convenient liquid water conditioner simplifies mineralization of pure reverse osmosis water. Reverse osmosis or de-ionizing filtration effectively removes dissolved solids, including minerals necessary for aquarium fish health (osmoregulation). This proprietary blend of salts replenishes these important minerals lost during the production of purified ro/di water. Seachem replenish restores general hardness (gh) using a balanced blend of both “soft” (sodium, potassium) and “hard” (calcium, magnesium) salts. Restoration of mineral content is essential since a complete lack of minerals will result in osmotic stress. 250 Ml treats 500 gallons. Directions: add 5 ml (1 capful) replenish to 40 l (10 us gallons) to raise gh by 1 meq/l (2. 8 Dgh). Recommended restoration level into di or ro water is 1-2 meq/l which is 5 ml per each 20-40 l (5-10 us gallons).