The bacteria quickly develop a natural microflora and a functional nitrogen circulation sera nitrivec prevents the accumulation of ammonia and nitrite since the bacteria in sera nitrivec are attacked by chlorine and other disinfectants the water must be prepared with sera aqutan an hour before the application of sera nitrivec 100 ml suffices for 400 liter aquarium water 500 ml suffices for 2000 liter aquarium water 5000 ml suffices for 20000 liter aquarium water