Filter material for the removal of silicic acid (silicate) in fresh and marine water to prevent diatoms Rinse, fill in filter bag (enclosed) and place in filter. Rinse after one to two weeks Diatoms can form brown unsightly deposits on gravel, decoration material and plants Silicate content can be checked with silicate test. Result: values below 0.4 mg/l silicate prevent diatoms Guaranteed efficiency: binds up to 30,000 mg silicate (SiO2)/ kg. Including net bag and sealing clip