Causative agent: Amyloodinium ocellatum — dinoflagellate parasite
Marine Velvet, caused by Amyloodinium ocellatum, is arguably the most dangerous disease that can enter an Australian saltwater aquarium. This dinoflagellate parasite attacks the gills first — often before any external signs are visible — and can kill an entire collection of fish within 24 to 48 hours. By the time hobbyists notice the characteristic gold or rust-coloured dusty coating on a fish's body, the disease is already well advanced. Urgent action is essential: affected fish must be moved to a hospital tank immediately and treated with chloroquine phosphate, which is available from aquarium specialist suppliers and veterinary clinics in Australia. The display tank should be left fallow for at least eight weeks. Because marine velvet so closely resembles marine Ich, any suspected outbreak should be treated with maximum urgency. Australian reef keepers are strongly advised to quarantine every new fish purchase for a minimum of four to six weeks — this one practice can save an entire collection.
Symptoms
- •Velvety yellowish-gold dust on skin especially near gills
- •rapid breathing
- •fish swims into powerhead flow
- •lethargy
- •loss of appetite
- •skin lesions
- •sudden death
Treatment
- •Chloroquine phosphate (treatment of choice)
- •copper-based treatments
- •freshwater dip
- •acriflavine
- •remove fish to quarantine tank immediately
Australian Medications
- •Chloroquine phosphate (via aquarium vets/specialty suppliers in Australia)
- •Copper Power
- •Seachem Cupramine
Commonly Affected Fish
- •All marine fish
- •tangs and surgeonfish are highly susceptible
- •clownfish commonly affected
Important Notes
Acts faster than any other common marine disease. Start treatment immediately — do not wait for confirmation. Tank fallow period: 8+ weeks.
