Silicate supports the growth of diatoms in marine water aquariums. sera marin silicate clear easily and permanently binds silicate. sera marin silicate clear is delivered with a practical filter media bag. Briefly rinse with running water before use, then simply place in a filter or a place with good water circulation. Remains active up to three months, depending on the silicate level. 500 g (1.1 lb.) are sufficient for an aquarium holding 200 – 400 liters (53 – 106 US gal.). Tip: The sera SiO3-Test kit allows to reliably monitor the silicate level.