Red Sea Test Lab Ammonia, Nitrite, and Nitrate Test Kits
Introduction to the Nitrification Process
As fish digest their food they produce ammonia as a waste product. In solution the total dissolved ammonia changes between two forms, the toxic ammonia (NH3) and the relatively harmless ammonium ions (NH4+) according to the pH and temperature of the water.
If no measures are taken, the toxic ammonia will rapidly increase to lethal levels in the limited volume of the aquarium. Bacteria of the genus Nitrosomonas and Nitrobacter oxidize ammonia through nitrite (almost as toxic as ammonia) to nitrate (which is nontoxic to fish). This oxidation is known as the nitrification process. The application of bacteria in water treatment is called
biological filtration (bio-filtration). In an aquarium with a mature bio-filter, the ammonia (NH3) is quickly converted into nitrite (NO2), which is thereafter converted into nitrate (N03).
Nitrate is relatively harmless to freshwater fish, although high concentrations will promote algae growth in the aquarium. If a de-nitrification filter is not used, the nitrate concentration can be kept within reasonable limits by regular water changes. The Nitrate level can be monitored using Red Sea's Nitrate Mini-Lab Test (item #27323).
Ammonia
As fish digest their food, and as bacteria break down uneaten fish food and other organic matter, ammonia is set free into the aquarium water.
In solution, the total dissolved ammonia changes between 2 forms, the toxic ammonia (NH3) and the less harmful ammonium ions (NH4) according to the pH and temperature of the water.
A percentage of the ammonium ions change as the pH increases, to the more toxic ammonia. Consequently, in marine aquariums with pH 8.1-8.4, ammonia will present a more serious problem than in freshwater tanks with pH around 7, since more toxic ammonia as low as 0.01 ppm, already show negative effects on fish, while 0.1 ppm can be deadly to some species.
When to Test for Ammonia?
New Aquariums
In a newly set up aquarium high levels of ammonia followed by high levels of nitrite is a normal phenomenon. As the new aquarium and the filter develop,
nitrifying bacteria begin to break down the toxic ammonia to a safe level, however, it takes slightly longer for the bacteria to develop in sufficient quantities to transform the nitrite into nitrate. Regular daily testing of the ammonia and nitrite is very important in a newly set up aquarium for the first two to four weeks. Only this will tell you when your bio-filter is mature and when it will be safe to put (more) fish into your aquarium.
Established Aquariums
Even low ammonia levels stress and weaken the fish, which makes them more susceptible to parasitic infections such as Ich. Ammonia poisoning is usually displayed by acute symptoms of fish swimming very rapidly, as in a panic; or breathing very rapidly; or jumping out of the water. The chronic symptoms are gill and skin damage and sometimes color fading. At the first sign of any of these symptoms test for ammonia. Ammonia levels may rise in older aquariums when the filter substrate has been damaged; for example, after administration of a medicine. Also, a blocked or fouled filter, as well as decaying matter in the tank, may give rise to toxic ammonia levels.
Nitrite should be tested when a malfunctioning biological filter is suspected. After a long period of time, the filter can get dirty, causing an oxygen shortage leading to high nitrite levels.
Recommendations
The toxic ammonia level in an established aquarium can be lowered by reducing feeding to an absolute minimum. Remove any decaying material and, if possible, as many of the fish as you can. If a blocked or fouled filter is the suspected problem, the majority of the filter material should be removed and cleaned allowing a new population of bacteria to grow. Since the filter must re-mature, we also advise that you monitor the nitrite level.
Note: When making water changes, ensure that the new water has a lower pH than the aquarium water. If the replacement water has a higher pH, the overall effect could be to increase the concentration of toxic ammonia (NH3).
Directions for Ammonia Test Lab- Check and write down pH and temperature of the aquarium water you wish to test.
- Fill a clean test tube with 3 ml of water to be tested (to the 3 ml line on the tube).
- Rapidly add 11 drops of Ammonia Reagent A. Immediately close the test tube with the stopper and shake vigorously for 10 seconds.
- Open the test tube and add 4 drops of Ammonia Reagent B. Close it with the stopper and shake gently for 10 seconds.
- Open the test tube and add 4 drops of Ammonia Reagent C. Close it with the stopper and shake gently for 10 seconds.
- Wait 15 minutes for the color to fully develop.
- Compare the color with the color scale by holding the test tube in a vertical position, 8" from a white background.
- Read off the ppm value of the color that is closest to the sample in the test tube. This is a measure of the total dissolved ammonia level.
- Use the table on the directions that come with the test kit to calculate the level of toxic ammonia. For marine aquariums, and reading of 0.25 ppm of total ammonia indicates a toxic level.
- Rinse the test tube with clean water after each use.
Introduction to Nitrite
As fish digest their food, and as bacteria break down uneaten fish food and other organic matter, ammonia is set free into the aquarium water.
New Aquariums
In a newly set up aquarium a high nitrite level is a normal phenomenon. It means that the nitrosomonas bacteria have started the nitrification process and produce nitrite out of ammonia. Nitrobacter is, however, not yet present in sufficient quantities to transform nitrite into nitrate. In a newly set up aquarium, we advise that you test for nitrite daily for at least two weeks.
Only this, together with testing for ammonia (use Red Sea's Ammonia Test Lab, item #27321), will tell you when it is safe to put (more) fish into your aquarium. After this two-week period, especially in the marine aquarium, one should start testing for nitrate, using Red Sea's Nitrate Test Lab (item #27323).
Established Aquariums
Nitrite should be tested when there is suspicion of a malfunctioning biological filter. After a long period of time, the filter can get dirty causing an oxygen shortage leading to high nitrite levels. Since in this case toxic ammonia can also be present in the aquarium, it is advisable to test for ammonia, using Red Sea's Ammonia Fresh Test (item #27321).
Directions for Testing Nitrite- Fill a clean test tube with 8 ml of water to be tested (to the line on the tube).
- Add 10 drops of Nitrite Reagent A. Close the test tube with the stopper and shake gently.
- Open the test tube and add 6 drops of Nitrite Reagent B. Close it with the stopper and shake gently.
- Wait 1-1/2 to 2 minutes for the color to develop.
- Open the test tube and look down through the open top of the test tube while holding it 8" above a white background and compare the samples with the color scale.
- Read off the ppm value of the color that is closest to the sample in the test tube.
- Rinse the test tube with clean water after each use.
Recommendations
A concentration as low as 0.1 ppm is already harmful to many marine invertebrates. Concentrations above 0.3 ppm are harmful for marine and freshwater fish. A typical behavioral symptom of acute nitrite poisoning is listlessness of the fish.
Lower nitrite levels stress and weaken the fish, making them susceptible to parasitic infections such as white spot.
The immediate short-term measure should be to change 20% of the aquarium water every day.
For the marine aquarium, we advise changing the water using Red Sea's Red Sea Salt (item #159683), until the NO2 level drops below 0.2 ppm. Red Sea Salt is especially useful in emergency situations like this, since it can safely be used immediately after dissolving, the pH and alkalinity being at the natural level. At the same time, we recommend to remove fish if possible, reduce feeding, clean the filter and inoculate it with some fresh material out of a good working biological filter, or use a freeze-dried bacteria preparation.
A value of 2 ppm is already very bad for any aquarium. Should you, however, require an accurate reading of a nitrite level higher than the range of this test:
(2 ppm), you should dilute the sample as follows:
- Mix 2 ml water sample with 6 ml distilled water.
- Perform the test as above.
- Multiply the result by 4.
Nitrate
Introduction to Nitrate
Ammonia produced by fish as a waste product is oxidized by aerobic bacteria in the biological filter, first to nitrite (NO2) and further to nitrate (NO3). In nature, a complete nitrogen cycle exists where plants utilize nitrate as a food source, thus maintaining the very low nitrate level found in unpolluted water.
In the aquarium, we create a one-way system rather than a nutrient cycle. The plant growth is mostly insufficient to use up all the nitrate introduced by the fish food. In most aquariums, especially in marine aquariums, nitrate will slowly accumulate so that unnaturally high concentrations are reached.
In the reef aquarium, corals and other invertebrates react distressfully to high nitrate levels and will eventually die. Nitrate will also act as a nutrient for plants that we do not desire. High nitrate levels cause the development of blue-green algae and hair algae. Fish may eventually become stressed and weakened by the NO3 pollution, which makes them more susceptible to parasitic infections. The nitrate concentrations should be tested every week. This is especially important in the marine aquarium.
