Rapid gill movements, and swollen or discoloured gills. The fish are likely to stop feeding and may
gasp either at the surface or laying motionless on the bottom.
The disease can be caused by infections of fungi, bacteria and parasites, and poor water quality is
likely to be a contributory factor.
An improvement in water quality may be the first step in treatment - avoid overfeeding and overcrowding, and carry out
frequent partial water changes. Use a water conditioner during water changes to avoid irritation of the gill membranes by chlorine.
It may be necessary to add an anti-bacterial to the water. If gill parasites are suspected, it may be necessary to treat with
formalin or copper based medications.