What is nitrite?Nitrite is the intermediate product in the nitrification process. Nitrite originates as a waste product produced by nitrifying bacteria as a result of processing ammonia. It is commonly encountered in newly set up aquaria, where there has been a significant increase in the number of animals in the aquarium, or if the filter has been disrupted.Why test for nitrite?Due to the presence of salt, nitrite is much less toxic to marine organisms than freshwater animals. Filtration bacteria in a well-established marine aquarium process nitrite as quickly as it is produced. The presence of nitrite therefore is an indicator that the equilibrium of the aquarium has been disrupted. Testing for nitrite regularly can help quickly assess the health of a marine aquarium before a problem becomes harmful to fish and marine invertebrates.What is the correct nitrite level in my aquarium?A healthy, mature aquarium should have 0 mg/l nitrite at all times. Any positive nitrite reading in an established aquarium likely indicates a problem with the aquarium and should be addressed.What to do if the nitrite level is wrong?If any nitrite is detected in your aquarium, determine the cause for the elevated nitrite (e.g. changes in stocking density, overfeeding, filter maintenance etc). Monitor livestock for changes and ill-health and carry out partial water changes to dilute nitrite if necessary.How to test for nitrite? Add 5 ml of water to be tested into the test tube provided. The middle mark on the test tube indicates 5 ml. Add 5 drop of the nitrite reagent to the test tube, cap the test tube and then shake. Wait for 2 minutes for the colour to develop. Once the 2 minutes has elapsed, view the test tube from the side and compare to the colour chart to determine the amount of nitrite present in the water. N.B. Colour will continue to develop after 2 minutes. Therefore, read the nitrite test immediately after the two minutes has elapsed. Attempting to read this test significantly after this time period may result in falsely high readings.
