WHAT EVERY AQUARIST AND POND KEEPER SHOULD KNOW ABOUT AMMONIA TEST KITS...

KPD-62
Interpreting ammonia readings has many users confused, including the experts. It is worthwhile to review the following information to help better understand what ammonia test kits and their readings are all about. First, you should know that what is generally referred to as "ammonia" is in two forms: un-ionized ammonia (NH 3 ) and ionized ammonia (NH 4 +). Ionized ammonia is relatively nontoxic while un-ionized ammonia is toxic to fishes and aquatic invertebrates, even in low concentrations.

Ammonia test kits commonly available in the aquarium pet industry read total ammonia: which include both unionized and ionized ammonia (NH 3 +NH 4 +). The unionized (toxic) form of ammonia is a part of the total reading, and two determinations have to be made to find the amount that is in the toxic form. Consult the paragraph entitled "The effects of pH and temperature on ammonia" at the end of this article for additional information on toxic ammonia levels.

There are two kinds of test kit readings; one for ionic ammonia and the other for ammonia nitrogen (a reading of the nitrogen present in NH 4 +). Some pond and aquarium test kits give readings as ammonia nitrogen, some as total ionic ammonia, and many don't explain how their readings are calculated. Older Kordon test kits read in units of total ammonia as nitrogen (N) for the salicylate kits and as ammonia ion for the nessler kit (as indicated in the instructions supplied with each kit). The latest generation of Kordon's ammonia tests kits read both the ion and as nitrogen.

What is the difference between test kit readings of ammonia ion and ammonia/nitrogen?
Many aquarists and pond keepers are perplexed by the use of the terms ammonia ion and ammonia/nitrogen (or ammonia as nitrogen), and do not know what the difference is between the two. The differences between the two terms are in how the chemical composition of the same ammonia molecules are being measured, which can be in two different ways, giving two different readings, each of which is correct. If you have a reading specified as ammonia/nitrogen it can be converted to ammonia ion by multiplying the reading by 1.3. If the reading is expressed as ammonia ion, it can be converted to ammonia/nitrogen by dividing by 1.3. For example, if the ammonia ion reading is 2.6 ppm, you can divide by 1.3 and you will get an ammonia/nitrogen reading of 2.0 ppm (2.6 ÷ 1.3 = 2.0). The conversion factor of 1.3 is based on the atomic weight proportions of nitrogen and hydrogen in ammonia (1.3 weight units of ammonia contain 1.0 weight units of nitrogen).

If the ammonia is measured as the total molecular weight of the molecules of the ammonia compounds in the water, which will be NH 3 + NH 4 +, the total amount of combined nitrogen and hydrogen atoms in the molecules are being measured as ammonia ion. If only the nitrogen atoms contained in the complete ammonia molecules are being measured and the measurement for the hydrogen atom is left out, the reading is for ammonia/nitrogen (N).

Most information in the aquarium and pond keeping hobby refers to ammonia as the total ionic ammonia so when you see the reference to ammonia as 0.8, for example, this usually means in aquarium and pond publications the total molecular weight for all the ammonia molecules. The number 0.8 means that the total weight is in ppm (parts per million) or mg/L (milligrams per liter), which for our purposes are essentially the same measurement. When the information provided does not indicate whether it is as ammonia ion or ammonia as nitrogen, there indeed can be confusion as to which is being measured. However, when you remember that the two readings are different by 1.3x, it may be possible to know to which of the two types are involved; at least for general aquarist and pond keeping purposes the readings are close enough together that it is not of major concern.

Why are there two different ways to refer to measuring the amount of ammonia in the water?
In scientific measurements of water quality in lakes, streams and oceans, the amount of nitrogen in the water, what ever the form, is an important measurement. Therefore, ammonia as nitrogen is widely used in the scientific literature. In biological laboratory research on living aquatic animals, the amount of total ionic ammonia present is important to know, particularly in considering the ammonia ions' effect on the physiological processes of the animals. Therefore, in this type of research, and in much of aquarium and ornamental pond keeping, it has been more important to measure ammonia as ammonia ion. But keep in mind that both readings are correct, and either reading can be directly acquired by multiplying or dividing by 1.3, respectively.

WHEN THE AMMONIA READINGS ARE MADE, WHAT DO THEY MEAN?
This question is often asked by aquarists and pond keepers wanting to know what the significance of their readings really are. Put simply, it is important to keep the level of ammonia as low as possible in the water, because it is toxic to fishes and aquatic invertebrates (toxic means poisonous; stressful but not necessarily lethal) . Even levels below 0.5 ppm (0.5 mgL) are toxic or enfeebling to many aquatic animals.

To immediately get rid of the ammonia in the water use Kordon's AmQuel ® or AmQuel® Plus(which quickly and permanently combine with the ammonia molecules to form new, non-toxic molecules, see KPD-51), or make partial or whole water changes. Over time, a properly set up biological filter will control ammonia build up. For specific aquatic animals check the technical aquaristic literature for their tolerance to ammonia. In general: Many of the hardiest fishes cannot survive toxic ammonia levels above 3.0 ppm (= mgL); sick fishes succumb at lower toxic ammonia levels than healthier fishes; most marine animals have a much lower tolerance to ammonia than freshwater animals, although many crustaceans (crabs, shrimp, lobsters) can stand 9.0 ppm and higher levels of toxic ammonia. To keep on the safe side use Kordon's AmQuel or do water changes as soon as you see 0.2 ppm or more total ammonia in the water.   Aquarium fishes should be kept at 0.25 ppm or lower, and some are adversely affected at as low as 0.5 ppm

WHERE DOES THE AMMONIA COME FROM?
Uneaten food, dead and decaying animals and plants, as well as the fecal, urinary and respiratory waste products of the aquatic animals are broken down into ammonia by heterotrophic bacteria in a process called amonification. A secondary ammonia source is tap water. Municipal water supplies often have high levels of ammonia added to the water combined with chlorine to produce chloramine. Chloramines are used to control bacteria and viruses which are highly toxic to aquatic animals. It is important for fish keepers to know whether or not chloramines are being used in their tap water, contact the local water supplier for information. Chloramines are extremely stable and will not "gass off" like chlorine. For information on dealing with chloramines see the AmQuel Product Data Sheet KPD-51. Whatever the source of ammonia in the water, it exists in a balance between ionized and un-ionized, converting back and forth depending upon the pH and temperature of the water. Ammonia (that is not combined with chlorine) is normally converted to nitrite and ultimately nitrate by naturally occuring nitrifying bacteria. This action prevents the buildup of potentially lethal ammonia concentrations in the water. See KPD-64 on BIOLOGICAL FILTRATION . If anything happens to the water that is detrimental to these bacteria (low alkalinity, low oxygen level, addition of antibiotics, etc.) the bacteria will become dormant or die, and the ammonia level in the water will immediately increase. Therefore, the regular use of Kordon AmQuel Plus, such as dosing once a week to eliminate all toxic nitrogen compounds is recommended, as is monitoring of aquariums and ponds by use of water quality test kits is very important.

WHAT IS THE EFFECT OF pH (ACIDITY/ALKALINITY) AND TEMPERATURE ON AMMONIA?
If you want to be more exact in assessing whether the amount of ammonia in the water is in the toxic form or not, it is necessary to measure the pH as well as the ammonia, because the pH of the water determines how much of the ammonia is in the un-ionic (toxic) form. Dependent upon the pH of the water, the ratio between ionized (nontoxic) and un-ionized (toxic) ammonia changes rapidly. The ammonia molecules are in balance between the nontoxic ionized and the toxic un-ionized; the higher the pH the more ammonia is in the toxic form; conversely, the lower the pH the less ammonia is in the toxic form. Temperature also plays a part in determining how much of the total ammonia molecule is in the toxic form; the higher the temperature, the more toxic the ammonia.

Kordon has created a chart of ammonia tables that show how to determine the amount of toxic ammonia in a given sample of water when the pH and temperature of the water and the amount of total ammonia are known. Once test kit readings are made of the ammonia, pH and temperature, the exact amount of ammonia in the toxic form can be determined. This chart also points out how pH and temperature can have a dramatic effect on the amount of toxic ammonia present in an aquarium or pond. For example, if the ammonia reading is 0.5 ppm (mg/L), if the pH is 7.0 and if the temperature is 73.4° F then the amount of toxic ammonia is .0025; the amount of toxic ammonia in this sample is below a harmful level for most aquatic animals. If only the pH were raised to 8.0, the amount of toxic ammonia would also rise to .0218 ppm (mg/L) which is a harmful level for many aquatic animals. This result would indicate that Kordon's AmQuel or AmQuel Plus should be added to the water to eliminate the toxic ammonia, or that a water change should be made. Testing should be continued to be sure that harmful levels of toxic ammonia do not recur. Click here for access to the AMMONIA TABLES

When using non-electronic colorimetric tests kits, including pH, keep in mind that many have, at best, an accuracy range up to plus or minus 10%. Kordon's Aqua·Tru Test Kits are accurate at the most accurate range within plus or minus 10%.

WHY ARE THERE TWO KINDS OF AMMONIA TEST KITS, NESSLER AND SALICYLATE?
Kordon's original colorimetric test kit used the nessler method, which measures in shades of amber from 0.6 to 3 ppm. Its advantages are that it reads a wide range of ammonia, and the test is fast to perform. The main disadvantages are the difficulties encountered when determining low levels of ammonia and the fact that the steps are farther apart than those in the salicylate method. Most ornamental aquarium and pond fishes can only tolerate a few ppm of ammonia at the very most and they need a test kit mainly reading below 1 ppm. The salicylate method test kits read between 0 and 1 ppm, the ideal range for ornamental pond and aquarium keeping. The colors range from a bright yellow (no ammonia) through various shades of green to blue-green to indicate the presence of ammonia; these colors are much easier to read than similar nessler's method test kits. Because of the way in which the AmQuels react with organics, salicylate test kits are the only type suitable for use with the Amquels.  The reagent used in nessler method test kits will react with AmQuel, producing a dark brown to black color, falsely indicating a high level of ammonia present in the test sample.

 For further information on ammonia test kits see their listings under products on the Kordon home page.  For an overview of Water Test Kits see Kordon Article THE TRUTH ABOUT WATER FOR AQUARIUMS AND PONDS, AND ABOUT WATER TEST KITS -- WHAT YOU NEED TO KNOW

 To order Kordon Water Test Kits click on the tab at the top of the page for NOVASHOP, then click on the Kordon tab, then click on Aquarium and Pond Test Kits.

To see table for conversion of ammonia ion to the un-ionized ammonia click here UN-IONIZED AMMONIA (NH 3 ) TABLE

For additional information on the Kordon AmQuel products, click here for AmQuel, and click here for Amquel Plus.

Original U.S. and foreign patents for AmQuel, now superceded by what has been developed for AmQuel Plus, patents pending:
U.S. Patent No. 4666610 - European Patent No. 0203741 - Canadian Patent No. 1300286 - Japanese Patent No. 1850992. 

© 2007, Novalek, Inc.