© Beverly’s Pet Center, Inc. 2014
Handling High Ammonia Levels
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High ammonia levels are a normal and unavoidable occurrence in new tanks. Other common causes of
high ammonia levels are overfeeding, adding too many fish, or medications that reduce the effectiveness of
the tank's natural ability to break down waste (nitrifying bacteria). The best method of dealing with high ammonia
levels in an aquarium is prevention. The obvious being stated, let's tackle a course of action for those times when
it is too late for that brilliant advice.
There are numerous ammonia removal products available that will provide almost immediate, temporary relief for the
inhabitants of the tank. We use and recommend Prime from SeaChem Labs. Ammonia will be altered to a non-toxic chemical,
but will still fool any Nessler Reagent based ammonia test kit, thus giving a false positive reading. Use a sodium salicyliate
ammonia test kit (Sea-Test or Dry-Tab) to obtain an accurate reading.
The use of an ammonia remover only provides short term emergency relief, but may be very helpful if the fish are
obviously stressed out. Partial water changes can also be used to provide quick, short-term relief of high ammonia levels. Be
aware of the fact that city water sources may contain ammonia levels as high as the water you are trying to correct. Reverse
osmosis or de-ionized water is ideal. If you use city water we suggest that chlorine/ammonia removers be used at 2 - 3 times the
manufacturer's recommended dose.
In freshwater tanks zeolite (Ammo-Chips), an ammonia removing resin, may be used in the filter as a slow, steady source
of ammonia removal. This is only effective for freshwater tanks. The resin does not have unlimited capacity to remove ammonia
and when levels are high it may become exhausted quickly. There is no way to tell when it has reached this point, so replace or
recharge frequently in high ammonia situations.
The long-term goal in ammonia reduction is to build up the biological filter, which is composed of the good bacteria, which
break down ammonia. We can help to accelerate this process with additives that are enzymes and nitrifying bacteria cultures.
They are available in many different concentrations and prices under such brand names as Nite-Out II, Cycle or Fritz-Zyme. Nite
Out II from Microbe Lift is the standout, using live bacteria cultures and we find it to be extremely effective. These products may
be used generously and regularly in periods of high ammonia.
Reducing the amount of waste being produced in the tank is very important at this time. This will allow the biological filter
to catch up faster and get the ammonia levels down. Feeding is the key here. Overfeeding is the most common cause of
ammonia problems! Skip one or two days feeding completely, then feed only one or two flakes per fish, once a day. Continue
this pattern until ammonia levels drop to zero and remains there. Many people are concerned that the fish will starve, but this is
an unnecessary worry. Most fish (except for very young babies) can handle missing a few meals without a problem. Lowering
the ammonia levels is a priority at this time, and it will do more for the health of the fish than food will. When the tank is stabilized
you can slowly increase feeding as long as ammonia levels remain at zero.
Don't Forget these Things!
Never add fish when ammonia levels are high. This would be a death sentence for them and decrease the odds for
all the other inhabitants of the tank.
Do a body count. Make sure there are no dead fish hidden around. Decaying bodies will make ammonia levels soar.
If the tank has live plants, remove any decaying or dying specimens.
Vacuum the gravel bed. If there is uneaten food lying around (from your old feeding habits) or if you stir the gravel
and clouds of detritus occur, this may be the source of an ammonia problem. If you are not familiar with gravel
cleaning techniques, check with one of our aquatic people and they will be glad to explain them.
Important notes on ammonia and pH
Often, when ammonia levels rise in an aquarium, the pH will drop. It would be a logical assumption to attempt to correct
this situation by raising the pH to normal levels. This would be logical, but it is far from correct and in fact could be deadly to your
fish. Ammonia takes two forms in water, free ammonia and ammonium ions, with free ammonia being the more toxic form. A pH
increase of one unit causes the percentage of free ammonia to increase by about ten times. Put simply, as pH increases
ammonia becomes more toxic to the fish.
It is usually best to leave a low pH alone while fighting high ammonia levels. The fish in the tank have slowly become
accustomed to the lower pH and you are not about to add any new fish at this time! It is difficult to try to maintain the normal pH
levels when ammonia is high. This means the pH drops, then you raise it, then it drops again and you raise it again. Can you
see another problem here? The constantly changing pH is further stress on fish that are already lining up for some Valium. This
leads us to our new logical conclusion, leave the pH alone until ammonia levels drop, then slowly (.2 every 12-24 hrs.) bring the
pH back to appropriate levels.
When you are faced with high ammonia levels, use some or all of the methods outlined here. Then, be patient! Well-
established tanks will usually respond quickly and ammonia levels drop off in days. In new aquariums ammonia will be present
for several weeks. This is normal. You can minimize problems by starting off with a light load of fish and feed lightly. I cannot
stress this point enough. With young children, be sure to supervise feeding time until you have established a proper routine.
When the new tank has stabilized and ammonia levels are zero you may safely begin increasing the load on the tank. Load is
biological load, or the amount of waste that needs to be broken down. Adding fish or increased feeding is additional load on the
tank. This is where patience will save you from lots of problems!
Stress from poor water quality wears down fish's immunity. If the poor water quality itself does not kill the fish, it will leave
them open to any number of diseases by weakening them. Always monitor fish closely during a period of high ammonia for
symptoms of common illness. Good water quality is the best prevention there is.
The staff at Beverly's are available to assist with any questions or problems you may have. Our goal is to
keep you on the road to successful fishkeeping!