Marine Red Velvet Fish Disease

Of all the diseases and parasites that can attack fish, none are more deadly for marine fish then the dreaded Marine Red Velvet Fish Disease. Velvet is one of those aquarium fish diseases that can absolutely devaste your tank. If you think you see a red velvety color appearing on your fish, you will have to act fast. Below is a brief description about the disease, as well as what you can do to save your fish before it is too late. This is not to be confused with Fresh Water Velvet, which is also dangerous.

What Is Red Velvet and How Is It Caused?

Red Velvet is a parasite that strikes marine tanks so frequently that it is the leading cause of death among marine fish. The parasite enters the skin and lungs of the fish, and spreads very quickly, killing the fish. This makes the disease dangerous, as it can spread quickly to other fish. Fish Velvet frequently affects fish that are stressed out. This disease is caused by a dinoflagellate named Amyloodinium ocellatum. It is one of the worst pathogens affecting tropical marine tanks.

Symptoms Associated With The Disease

Red Velvet will strike at the skin and lungs of the fish. Breathing difficulties are the most recognizable symptoms. Reluctance to feed, weird smimming behavior and rubbing against sand or other objects in the tank are also a giveaway. These symptoms are often accompanied by a dull velvety sheen on the skin of your fish.

How To Treat Velvet?

The disease has a very high mortality rate, and should be treated as quickly as possible. The most common treatment is copper. In small doses, copper is non-toxic to the fish but excellent at getting rid of the Velvet Disease. As an important note however, you should not use copper near invertebrates, as it is extremely toxic to them. It is best to quarantine them prior to introducing copper to the tank, and then only bringing them back after the tank has been cleaned thoroughly. You are looking for between .15 and .2 parts-per-million of copper in the water. In addition, you will want to treat the water for roughly half a month. We offer a much better solution for treatment, our drops can be applied directly to your tank without the need to relocate or quarantine your invertebrates.


Preventing the disease is not difficult. Keep your fish as stress-free as possible. The disease most often appears when new fish are introduced to the tank. As a result, if you are afraid of the Velvet Disease, then quarantining the fish before to putting them in your tank is a good way to see if the new fish are infected.