Velvet disease (also called gold-dust, rust and coral disease) is a fish disease caused by dinoflagellate parasites of the genera Amyloodinium in marine fish, and Oodinium in freshwater fish. The disease gives infected organisms a dusty, brownish-gold color. The disease occurs most commonly in tropical fish, and to a lesser extent.
Scratching against hard objects.
Loss of appetite and weight.
Loss of color.
Rapid, labored breathing.
Use anti Velvet medicines according to the tank size (Dosage 5 ml per 25 liters)
Sodium chloride (table/sea salt) is believed to mitigate the reproduction of velvet, however this treatment is not itself sufficient for the complete eradication of an outbreak. Additional, common medications added directly to the fish's environment include copper sulfate, methylene blue, formalin, malachite green and acriflavin, all of which can be found in common fish medications designed specifically to combat this disease.