Rapid test for determining the nitrite content in freshwater and saltwater aquariums and ponds. Nitrite is a toxic nitrogen compound that forms when the bacterial balance is disturbed or when a new aquarium is set up. The test shows the exact nitrite content of the water. Laboratory comparison system to compensate for the inherent colour of the water: Fill a glass vial with sample water, add reagents to a vial, place the vial in the holder and read the values from the colour chart. Application: When setting up a new freshwater aquarium, colour daily for 3 weeks. Once a week when setting up a marine aquarium for the first time. For use in the event of fish diseases or fish mortality. Package contents: 1 nitrite test for approx. 50 measurements, including 2 reagents, 2 glass vials with screw cap, syringe, comparator block and colour scale. Reagent refill available separately.