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Ammonia Stress and Ammonia Poisoning

What Are the Signs of Ammonia Stress?

(The First Tank Guide)

Ammonia poisoning is a very real threat to your fish, especially when the tank is new and is still cycling or if the tank has been stressed and the biological filter has been upset or removed.

Ammonia stress is caused by two occurrences in the aquarium chemistry. First is the build up of toxic ammonia and nitrite in the water. This directly affects the fish and can have a number of harmful side effects - from increased disease susceptibility to organ failure. The second component of ammonia stress is the displacement of oxygen in the water by the ammonia. The more ammonia is in the water, the less oxygen is available to your fish and your biological filter. Not only does this further stress the fish and pose a risk of suffocation, but it also decreases the efficiency of the biological filter. This is among the reasons that water changes are so important when your tank is cycling to insure a smooth and headache free cycle.

What is the Difference Between Ammonia Poisoning and Ammonia Stress?

Ammonia stress and ammonia poisoning are really the same thing. It is also referred to as nitrogen poisoning or nitrogen stress as well. Generally, though it is not referred to as 'poisoning' until you have actually lost a fish. Until that time, it is referred to as ammonia stress.

Signs of Ammonia stress

The signs of ammonia stress are usually pretty easy to detect, especially if you are paying attention to your fish regularly.

This list of symptoms is by no means exhaustive of the symptoms of ammonia poisoning or ammonia stress. However, these are many of the more common symptoms, and generally they will show up in more-or-less this order. However, since, especially in new or particularly small tanks, the ammonia level can rise quite quickly, particularly if the tank is overpopulated, you may see a very rapid succession between these symptoms.

What Do I Do for Ammonia Stress or Ammonia Poisoning?

Actually, this is quite simple - do a water change. You may be tempted to use an ammonia remover, however, this should almost always be avoided because this can have long-term negative side effects on the tank, and is rarely helpful for very long.

A water change, however, will remove some of the excess ammonia from the aquarium (provided you are not using source water with a lot of ammonia in it), and will allow the biological filter to begin to process the excess waste while relieving the stress on the fish.

when the tank is still cycling, you will need to perform these water changes regularly to keep the ammonia from building up and prevent 'new tank syndrome,' which is usually just ammonia poisoning.

What if Ammonia Poisoning Keeps Coming Back?

Once the tank has cycled, you should no longer be seeing signs of ammonia stress or ammonia poisoning. If you are seeing similar stress symptoms, there could be another chemical problem with your water, or your fish may be sick.

However, if the ammonia poisoning keeps coming back, you may have another problem. The most common is overpopulation, though over feeding can also be a cause of ammonia poisoning. Insufficient filtration can be another contributor to high ammonia levels in the fish tank. If you repeatedly run into ammonia problems, provided the tank is cycled, you should look first into your tank population, then at your feeding habits, and then into your filter maintenance, tank cleaning, chemical use, and the overall capabilities of your filter.




"I read your web page. It's really fantastic. You have done a wonderful job. Your page has solved almost half of my questions. It's the only web page that is updated and well informed so often. I love to go through your pages again and again. Thanks, Keith, Thanks. "
April 26, 2005
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"Thanks for the info, very helpful, and you have dispelled the myth about fish growing into tank size. Shame though, you could end up with an interesting rectangular fish. "
June 9, 2003
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