Aquarium Fish & Gill Diseases

Aquarium fish are vulnerable to several common diseases, including those that affect the gills. Many diseases are treatable using chemicals or by changing the water conditions in the tank. Many aquarium fish diseases are caused by parasites or bacterial infection. Diseases will usually produce visible symptoms, either in fish behaviour or appearance. Recognizing symptoms can help aquarium owners diagnose and treat a condition.

  1. Velvet Disease

    • Velvet disease, sometimes known as gold dust disease, is a parasitic condition that can affect aquarium fish. Velvet can be very contagious and is often fatal. The name is derived from the light brown dust that appears to cover the body of an infected fish. The disease can cause respiratory inflammations around the gills, according to Wet Web Media.

    Gill Flukes

    • Gill flukes are parasites that live in the gills of some aquarium fish. Cichlids are particularly prone to gill flukes, according to Cichlid News Magazine. Early signs include listless behaviour and rubbing the gills against the sides of the tank. Infected fish may have mucus develop around the gills, as well as small, ragged pieces of protruding gill. Flukes are generally not too much of a problem in small numbers. However, infestations can occur in some aquarium populations. Increased salt content in the water can often help reduce fluke numbers, though this should be carefully controlled in freshwater tanks.

    Ich

    • Ich is one of the most common conditions in aquarium fish. The condition is caused by a parasite and can give the fish some breathing difficulties. Ich is quite easy to recognize. It produces white dots along the fish's fins and body--with each spot the location of a growing parasite. Ich that is focused on the gills may result in white spots inside the gills, not immediately visible from the outside.

    Columnaris

    • Columnaris is a bacterial infection that often first attacks fish around the gills. It's frequently the result of stressful aquarium conditions such as overcrowding, or low tank oxygen levels. The gills of infected fish will usually turn a light brown, getting darker over time, according to National Fish Pharmaceuticals. Death can occur within a few days if treatment is not administered.