Tetra Algetten for the prevention and long-term combating of algae. Algae have a negative effect on aquaria and can inhibit plant growth by consuming valuable nutrients. On a long-term basis, algae negatively influence the biological balance of aquaria. Mild, long-term effect due to water-insoluble tablets: the Tetra Algetten, which are housed in a holder, emit their agents over a period of approx. four weeks. Considerable reduction of existing algae after just 4 to 7 days.Dosage for Tetra Algetten:put 1 tablet per 10 litres of aquarium water (fresh water) into the holder and mount the holder inside the aqurium. Package content is sufficient for 120 liter.