Velvet (Oodinium)

What is Velvet (Oodinium)?

Velvet can appear a lot like White Spot except the spots or film are finer yellow, rust or gold dust in colour.

This parasite is a microscopic dinoflagellate (two little "whip like organs" or flagella used to propel the parasite through the water). It attaches to the skin of fish (then loses the flagella) in order to feed.

Initially it appears as small white dots (similar to ich) but is much finer giving it a "velvet" appearance. They can live without a fish host for up to 24 hours in the water.

This film may be difficult to see, but can be more easily detected by directing the beam of a flashlight on the fish in a darkened room. The parasite is most often seen on the fins and gills.

The fish may display rapid gill movement and be rubbing itself (flicking) on the surfaces in the tank. In the latter stages of the disease the fish will become lethargic, have a loss of appetite, weight loss and display rapid / laboured breathing.

What are the causes of Velvet?

The disease is caused by a protozoan parasite, and may be triggered by exposure to ammonia and nitrite, or excessive nitrate levels.

How to treat Velvet:

- Check your water conditions; chemistry as well as pH and water temperature.

- Slowly raise water temperature to 29C over the course of 24hours (in tropical tanks).

- Turn off the lights while treating.

- Do a 30% - 50% water change.

- Remove carbon from your filter while treating your tank. Carbon will absorb any medication that you place into the water.

- Add  aquarium salt 1 tablespoon per 20L. Make sure 50% water changes are done daily using this method.
Use this treatment on bettas or other surface breathing fish. (Caution with those scaleless fish. e.g. clown loach)

- Treat with Acriflavine.

This disease is very stubborn, and difficult to cure. There is a high chance the fish may not survive, so prevention is the best cure.