Ammonia ---- Or
"Water Management For The Neglectful Aquarist"
By Dick Van Hyfte
Quests for knowledge develop from the need to know. The need to know where ammonia is involved usually develops while watching your fish take their last breath.
That is the reason that I began to study ammonia. One of the first things I learned was that ammonia is probably the number one killer of aquarium fish. Further research taught me that the subject was more complex than I originally thought. Although I can now say that I have gained enough knowledge to deal with most ammonia toxicity occurrences, I know that certain phenomena can occur that will be beyond my understanding.
I will briefly discuss the effects of ammonia poisoning and the sources of ammonia within the aquarium. Knowledge of these subjects is essential to the aquarist if ammonia is to be dealt with effectively.
Ammonia Poisoning
Ammonia poisoning is very dangerous. Permanent gill damage was demonstrated in 4 week old fishes exposed to less than 0.1 parts per million of actual unionized ammonia. The toxicity does vary with the age and species of fishes. Other factors, particularly pH and oxygen levels, also affect toxicity. The relationship of pH to ammonia is shown in Table A.
Experimentation has shown that the liver, gills, skin mucus and blood vessels are damaged by ammonia. Gill damage seems to be the item that results in the most permanent disability. I also suspect a link with nervous system damage due to some type of osmotic shock, which seems to occur during ammonia poisoning, but this still requires investigation.
Secondary infections frequently follow ammonia poisoning. The damage can lead to bacterial infections, fungal infections, and parasite damage (most frequently this seems to be velvet).
Still another effect of ammonia is its growth inhibiting activity. Even traces of ammonia will slow fry development.
Sources of Ammonia
Ammonia can be introduced into the aquarium by more methods than is generally realized. I will number them for future reference.
(1) Fish excretion
(2) Decomposition of uneaten food.
(3) Decomposition of dead animals.
(4) Decomposition of dead plants (including some driftwoods).
(5) Conversion of the ammonium ion to ammonia during pH increases.
(6) The reduction of nitrate into ammonia.
(7) Sources external to the aquarium, i.e. gaseous ammonia
(8.) Chloramine water treatment by municipalities.
Elaborating on these sources:
Ref. #1: 80% of the ammonia, which initiates from fish and other aquatic animal's excretion, is released directly. The remaining 20% are released during the decomposing of the excrement similar to the effect exhibited in #2 through #4 following.
Ref. #2 and 3: Ammonia is released during bacterial activity, which breaks down the food and animal matter. This action may continue to break the ammonia into nitrites and then into nitrates which are "relatively" harmless. This activity is dependent upon the presence of bacteria known as Nitrosomonas and Nitrobacter, which take longer than most bacteria to establish colonies in the aquarium. Therefore, freshly set up tanks are more likely to have problems with ammonia from these sources than are established aquaria. These bacteria cease to function below 6.5. Since these bacteria are slow to establish themselves, a sudden increase in the animal population or feeding activity will cause an ammonia rise.
Ref. #4:The action here is similar to #2 and #3 except those bacteria that break down cellulose will release additional ammonia. Driftwood should be suspected when other sources are eliminated and ammonia continues to rise.
Ref. #5: The ammonium ion is present in large quantities in water of low pH. The pH to ammonia and ammonium relationship is shown in Table A. A rise in pH of a single point can cause the immediate release of an enormous amount of ammonia into the aquarium water. This rapid conversion of ammonium to ammonia is an unequaled "fast fish killer." This effect can't be over emphasized. Beware of making water changes on aquaria that have been neglected for a long duration.
The ammonium ion is very low in toxicity, thus lulling the aquarist into thinking that all is well within the aquarium. Concentrations of 20-30 ppm (parts per million) can easily be present in waters with a low pH. A rise of 0.5 in pH can cause a lethal dose of ammonia to be released. Although this phenomenon usually occurs during a water change, any rise in pH will produce the same result.
Waters that contain low carbonate hardness are quite unstable due to the lack of buffering effect of the carbonates. Some sources recommend a minimum carbonate hardness of DH 2 to 3 to maintain a good buffering capacity. It is not a bad idea to test your carbonate hardness to know whether or not your water is well buffered against pH shifts. Water that is not well buffered may require more careful monitoring.
Ref. #6: The reduction of nitrate back to nitrite and, finally, back to ammonia, does not seem to be well understood. Certain reductive factors must be present for this to occur. I would imagine that this danger is quite real within the aquarium. Frequent water changes and the availability of atomic oxygen are sound preventative measures.
Ref. #7: The external source of ammonia can be easily overlooked and is seldom suspected as being the culprit. Household cleaners containing ammonia and household pets are typical sources for ammonia external to the aquarium.
This danger can't be overemphasized. Ammonia has a strong affinity for water. Free ammonia is looking for your aquarium water to render it uninhabitable. This affinity has been dramatically demonstrated by some makers of anhydrous ammonia. It seems that, on occasion, maintenance personnel will unwittingly add water to ammonia tanks while cleaning them. Throwing even a small amount of water into an empty tank, and then capping it can produce a bizarre effect. The ammonia vapor is promptly absorbed into the water, creating a vacuum within the tank. The structural collapse of the tank is the embarrassing result.
Ref. #8: As if we do not have enough to worry about, state-of-the-art municipal water treatment calls for the addition of chloramines to drinking water. Removal of the chlorine component of Chloramine can leave lethal (for fish) levels of ammonia.
Testing for Ammonia
Most ammonia test kits are quite reasonably priced and are acceptable for our purpose. Accurate quantitative analysis, however, would require the purchase of some expensive equipment.
The low priced kits usually contain a version of Nessler's reagent. This test first raises the pH of the solution to put all ammonium ions into the ammonia form. This way, all ammonia is measured. A light yellow color, during testing, indicates that ammonia is present. An increase in the ammonia content causes a darkening of the yellow coloration until a high concentration causes a brownish color. Since the test only shows varying degrees of yellow coloration, accurate determination is not possible, but sufficient for our purposes.
TABLE A
(Adapted bibl. #1 & #2)
pH Vs. Ammonia/Ammonium
pH Ammonia Ammonium
% %
6.0 0 100
7.0 1 99
8.0 5 95
9.0 36 64
10.0 78 22
Even a small amount of ammonia can pose a threat. Since we are concerned with ammonia rather than ammonium, a pH test should also be run to determine the actual amount of ammonia present. Use Table A to determine the concentration. Remember, though, ammonium does represent a potential threat in the event of a pH increase.
Controlling Ammonia
Good aquarium management will usually serve to keep ammonia levels safe. All aquarists will, however, slip once in a while. Everyone should learn to recognize and be able to immediately react to ammonia poisoning symptoms. The neglectful aquarist that has managed to survive in the hobby for a considerable length of time will have developed techniques for dealing with this problem. Perhaps that is why I learned them so well.
Effective action usually entails taking first aid, removal of the water source, and, finally, the removal of the ammonia from the system. One additional step is to undertake a convalescent program for the victims.
First Aid
First aid needs to be delivered immediately when ammonia poisoning is suspected. The aquarist will then have time to determine whether the ammonia is indeed the culprit, so the next course of action can be plotted. Rapid breathing is usually the first sign of problems. The fins may also look a little "cloudy" in spots. Irreparable damage may already exist.
First aid is delivered in three steps. First, make atomic oxygen available to the victim. This is best accomplished by adding 3-4 drops per gallon of 3% hydrogen peroxide solution. Aeration is of no use here. Go immediately to the next step.
Decrease the ammonia within the system. Proceed cautiously with this step. Do not attempt to use ion exchange resins as they may raise the pH thus releasing more ammonia. Do not exchange or add any water that is higher in pH than the water within the aquarium. (If no other alternative exists, however, a radical change of 75% or more may lower the ammonia content enough to save the fish but the weakened victims may not be able to tolerate that radical of change.) Do add or exchange water that is the same pH or slightly lower. Go immediately to the next step.
Reduce the effects of osmotic shock and nerve damage. Dissolved noniodized salt should be added to a concentration of 1 teaspoon per gallon to fresh-water aquaria. Other means should be utilized if the aquarium contains fish that are sensitive to salt. Any of the water additives that will increase the electrolyte levels can be used. Try to find one that does NOT contain pH buffers since they might tend to increase the pH.
After these steps are taken, the next item on the agenda will be to determine whether ammonia is indeed the culprit. Even if it is not, the preceding steps will usually do much to relieve the stress. Test for ammonia as described previously, and, if found, proceed as described in the next part.
Removal of the Ammonia Source
This section is keyed back to the section entitled "Sources for Ammonia." Please refer to that section for a more complete understanding of the topic.
Ref. #1: Regular water changes will control ammonia from fish excretion. A well-established aquarium with a pH near 7 or above should have a functioning biological filter that will oxidize ammonia into nitrites and nitrates thus leaving the ammonia level near "0." Until a biological filter is established, regular small partial water changes will help to keep the ammonia under control. The "ammonia controlling filter materials" are of use during this phase. Overuse, however, may prevent an effective biological filter from becoming established.
Ref. #2: Remove uneaten food within a few hours of feeding. Do not overfeed.
Ref. #3: Remove dead or dying animals as soon as they are noticed.
Ref. #4: Remove dead or dying leaves from plants. Remove diseased and dead plants. Remove driftwood suspected of being the culprit. (the ammonia problem is not usually caused by driftwood, but be wary.)
Ref. #5: Avoid upward sweeps in pH. Test for ammonia in acid water tanks before making water changes. Match the pH of replacement water to the aquarium water prior to the changes or make very small changes when ammonium is present. Note that ammonia tests using Nessler's reagent will convert the ammonium ion to ammonia so that the total ammonia is measured.
Ref. #6: The reduction of nitrate to ammonia seems to be the product of a system that is really out of balance. The best way to overcome this problem is to tear down and reestablish the aquarium. Trickle filters, live plants, good water circulation, and frequent maintenance will reduce the reduction potential.
Ref. #7: The removal of ammonia sources external to the aquarium may require some adjusting of the cleaning person's methods. Do not use ammonia-containing products in the aquarist's household. The ammonia will find the water! Separate other animals from the aquarium room and keep cages and liter boxes clean. Pet shops take note! Keep the air pump away from the floor. Incidentally, many toxic fumes are either heavier or lighter than air. Keeping the air pump about 2/3 of the way from floor to ceiling is good practice.
Ref. #8: Plenty of companies make chloramine removers that are effective in removing both the chlorine and ammonia components. Test to be certain that you are using adequate treatment on the water before it is placed in the aquarium. Inadequate removal can cause more problems than just ammonia poisoning.
Medications and Ammonia
Many medications are responsible for the destruction of the biological filter. Whenever this occurs, the ammonia level will begin to rise. The best way to fight disease is to prevent it. Practice sound aquarium management and isolate new acquisitions. Keep disease out of the aquarium so that you will not have to risk the destruction of your biological filter.
Adding salt and darkening the aquarium can usually cure velvet. Clean all debris from the aquarium floor and continue salt treatments for 2 weeks after the disease seems to have disappeared. Do not use copper-based medications on this disease or your biological filter will die. Any treatment other than salt must be carried out outside the biologically stable aquarium. Do treat the aquarium with 1-2 teaspoons of salt per gallon even if the residents are treated externally to the system.
Ich can also be treated with salt and the raising of the temperature. Fishes that are particularly sensitive to Ich, may need additional medication but, once again, this must be carried out away from the biological filter.
Other Problems
If fish fail to respond to first aid treatments for ammonia poisoning, other poisoning should be suspected. This is likely due to heavy metal poisoning or the toxic effects of a disease process. The procedure for the fighting of heavy metal poisoning is to move the fish immediately to another container. Then set about to look for the cause. An ammonia test should be conducted just to be sure.
Summary
The control of ammonia is essential the well being of your aquarium fish. A thorough knowledge of the subject will allow you to experiment with water chemistry with a little more surety. I believe that the hobbyist needs to keep a basic kit containing the following:
(1) A copy of this article
(2) A bottle of 3% Hydrogen peroxide solution.
(3) An ammonia test kit.
(4) A container of water with a low pH.(or "pH down")
(5) Ammonia removal materials (such as Zeolite resin).
(6) Uniodized Salt.
(7) A spare aquarium.
(8.) A product that will increase the electrolytes within the aquarium.
Ammonia poisoning has never been given the status it deserves. Aquarists have taken the time to learn a great deal about diseases and water chemistry that does not have the potential to cause the problems that ammonia does. I hope that this article has placed ammonia into proper perspective.
References
Huckstedt,Guido -- Water Chemistry for Advanced Aquarists,
TFH publications, 1973.
Spotte, Stephen H. -- Fish and Invertebrate Culture,
Wiley Ineterscience, 1970.
