Phos Stop is an effective means of binding phosphate in the pond water and on the bottom and thus preventing natural pond problems. It is best to use it early in the year and repeat the dose every month. Also check the quality of the pond water and regulate the total hardness with GH Plus. The ideal GH value is between 8 and 12° DH. Oxygen deficiency can occur at high temperatures and with many fish. In this case, aeration and a partial water change are recommended. Phos Stop contains the active substance lanthanum and is a simple and effective solution to prevent pond problems.