PHOSPAT®️ is a filter cartridge with a granulate - made of phostake - which is able to bind phosphate extremely fast and reliably. Thus phosphate-containing water in swimming ponds, natural pools, lakes, fish and koi ponds, aquariums, wells and for fish farming is freed from phosphate in an environmentally friendly way and without chemicals. Perfect for untroubled bathing pleasure - and to create ideal living conditions for your fish.