Freshwater

Frequent Causes of Disease
There are many causes of disease that are not related to parasites and infection,
such as carbon dioxide poisoning, poor water quality, metal poisoning,
chemical poison, improper diet, overfeeding, and fright. These important
physical and social conditions should be monitored frequently.
Carbon dioxide poisoning
Symptoms: Listlessness; increased or rapid respiration — your fish may hang
near the top of the water.
Cause: Lack of oxygen; too much carbon dioxide in the water.
Treatment: Add more aeration to improve gas exchange at the water surface;
cut down on plant fertilization; check and correct any poor water conditions;
and carry out frequent water changes.
Poor water quality
Symptoms: The first sign is that your tropical fish are gasping for air at the
water surface of the tank and are generally inactive. Clamped or closed fins,
overall bad health, and poor coloration are a few more symptoms of incorrect
water quality.
Cause: Poor water quality due to infrequent water changes, poor filtration,
and overuse of standard chemicals.
Treatment: Make daily water changes until any high ammonia, nitrite, or
nitrate levels return to lower readings. Make sure the aquarium has enough
aeration and add an extra airstone or bubble disk if necessary. Make sure the
pH of the water is within the proper range (a couple degrees of what is
normal for the species).
Metal poisoning
Symptoms: Erratic behavior; paleness.
Chapter 11: Diseases and Treatments
Cause: Metal objects coming into contact with the aquarium water.
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