My fish are gasping…?
This is a sign of respiratory problems. The most common cause is some form of gill disease, but internal disorders such as heart disease can also cause respiratory problems. It is important to establish the cause and resolve any underlying problems before any treatments are used.
First check ammonia, nitrite and pH (Test kit) as unacceptable levels can cause gill damage. Check dissolved oxygen levels (cheap kits are readily available). The affected fish should be examined for signs of gill parasites and gill disease. This obviously requires a level of skill and experience and access to a microscope. Professional assistance should be sought if necessary. Treatment depends on the cause of the problem. Any suspicion of gill disease must be taken seriously and an accurate diagnosis made as the wrong treatment can exacerbate the situation