Replenish is a proprietary blend of salts designed to replenish physiologically relevant minerals that are removed by reverse osmosis or deionizing filtration. 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 in those species whose osmoregulation systems are adapted to a mineralized environment. Severe osmotic stress can result in osmotic shock which will lead to rapid death.