Clownfish are very bright, orange saltwater fish that originate from the warm waters of the Indian and Pacific oceans. Although they can sufficiently live in a home aquarium, clownfish can get sick just as any pet can.
Loss of Color or White Spots
If you have noticed white spots on the gills of your clownfish or loss of color in its patches, it may have White Spot Disease. If your fish is constantly resurfacing for air, this is a sign of clogged gills which is another symptom of White Spot Disease. Your fish will also scratch itself against objects in the aquarium if it has this disease.
If cysts are seen on your clownfish, accompanied by a velvety powder-like substance seen on the body, your fish may have Velvet or Oodinium. If your fish shows symptoms of having cysts accompanied by white mucus-like matter, it may have Brooklynella or Clownfish Disease.
Small Black Spots
Black Ich disease is characterized by small black spots over the fish's body. About the size of a pinhead, the spots are easy to see on light-colored areas of the fish's body. Other symptoms include development of pale body color, lack of appetite and lethargy. A clownfish with Black Ich will also scratch its body on the bottom of the aquarium or against other objects.