Amyloodinium is otherwise called the Marine Velvet. It cannot be classified as a plant or an animal as it has both of these characteristics. It is classified as dinoflagellates. Movement is a characteristic of animals and the use of photosynthesis is a characteristic of plants. Both of these are present in Amyloodinium. Amyloodinium affects the fishes in marine and brackish water. It mostly affects the gills and the skin of the fishes. Infection of Amyloodinium has also affected the fish food industry very much.

Amyloodinium has two flagella like a whip which is used to move around. There are different stages in the life cycle of Amyloodinium. Trophont, Tomont, and Dinospores are the stages in the life of Amyloodinium. In the Trophont stage is feeds as a parasite. It attaches itself to the fish with the help of rhizoids and feeds on the host. As it grows it comes to the next stage of life called Tomont at which its size will be around 350 micrometers. At this stage it disengages from its host and starts reproduction. Reproduction is by repeatedly dividing itself until there are 256 offsprings. To complete this stage it needs around 3 days after which it hatches tiny dinospores and these dinospores start infecting the host for about 15 days after which they go to the next stage in their lifecycle.

It is difficult to identify the signs of infection in fishes caused by Amyloodinium. Difficulty in breathing is a sign of the infection but it is hard to find it. Loss of appetite is another sign of infection. The fish that is infected would be rubbing it body on the sides of the aquarium or other objects in the aquarium and it is also a sign of infection by Amyloodinium. Swimming will be erratic when the fish is infected. Apart from all these behavioral signs you can find velvet like dust on the skin of the fish. This is reason for the name Marine Velvet.

Treating the fishes that are infected by Amyloodinium is a big challenge for the fish industry. None of the methods of treatment are effective in treating infection by Amyloodinium. The most common treatment is the use of copper in water. Water that has free copper at the level of 0.2 mg'l is used in treating fish that are affected by Amyloodinium. At this level of copper in water certain types of fish will be killed. So, prolonged treatment using this method is not advised. One of the other methods is to give a fresh water dip to the infected fishes. This fresh water dip will remove the Amyloodinium from the fishes which are in the stage of dinospores. You need several fresh water dip treatment to remove other stages of Amyloodinium. Chloroquine which is used as an antimalarial is used in the treatment of infection by Amyloodinium, but this compound is not approved by the FDA. Hence using Chloroquine is US is not possible for treating infections by Amyloodinium. Since treating fishes for Amyloodinium is not effective, avoidance is the better option. Hence the fishes that are coming in to the system should be quarantined for about 3 weeks.