The important plant nutrient phosphate is required only in small amounts. An over-supply creates algae problems. sera phosvec Granulat removes phosphates easily and safely with long-term effects in fresh and sea water aquaria. sera phosvec granules remain active up to three months, according to the aquarium size and the water pollution. Replace the granules if the capacity is used up (noticeable by an increased phosphate level). 500 g sera Phosvec Granulat binds approx. 12.5 g of phosphate.Do you have questions about this article ?