If your pond water is too soft, it is unhealthy as it causes the water to acidify quickly, especially if it rains a lot. A water hardness of 8-12°dH is required for an ornamental pond, the level for a pond with fish is even higher. The total hardness of water is determined by dissolved calcium and magnesium phosphates. If the value is too low, you should definitely take action. VijverTechniek GH-Plus increases the total hardness quickly and easily, and greatly improves the quality of the pond water. It stimulates the growth of oxygen plants and the development of microorganisms. A regular inspection of the water hardness is highly recommended because a certain hardness of the pond water is necessary for a stable and healthy pond. GH-Plus can be used for pond and aquarium water.