Disease + treatment guide

Marine Velvet (Amyloodinium)

Marine Velvet (Amyloodinium) guide for aquarists. Symptoms, treatment protocol, prevention, and when to escalate.

Marine Velvet (Amyloodinium) TL;DR

Affects: saltwater fish · Symptoms: gold dust appearance on body, rapid breathing, lethargy

Treatment: Aggressive copper treatment, hospital tank, treat fast - velvet kills in 24-72h

What is marine velvet (amyloodinium)

Marine Velvet (Amyloodinium) is a common aquarium disease/pest affecting saltwater fish. Recognizing it early and treating quickly is the difference between losing a single fish and losing an entire tank.

Symptoms to watch for

gold dust appearance on body, rapid breathing, lethargy. Watch for behavior changes (reclusive, refusing food, color loss) as early warning signs - even before visible symptoms appear, fish stress patterns indicate something is wrong.

Treatment protocol

Aggressive copper treatment, hospital tank, treat fast - velvet kills in 24-72h. Always treat in a separate hospital tank to protect invertebrates, coral, and beneficial bacteria. Follow medication protocol exactly - underdosing produces resistance, overdosing creates new problems.

Prevention

Quarantine new fish for 4-6 weeks before adding to your display tank. Stable parameters + appropriate stocking + adequate filtration prevent the chronic stress that makes fish susceptible to disease in the first place.

When to escalate

If symptoms persist beyond expected treatment duration, parasites/symptoms reappear after treatment, or the disease spreads despite isolation, escalate to a fish-specific veterinarian or experienced reef keeper. Aquatic veterinarians offer prescription medications (chloroquine, levamisole) not available over-the-counter.

Marine Velvet (Amyloodinium) FAQ

Is marine velvet (amyloodinium) contagious?

Yes - most fish diseases spread via water column or direct contact. Isolate infected fish in a hospital tank.

Can I treat in the display tank?

For most diseases - no. Copper kills inverts, antibiotics destroy beneficial bacteria. Always treat in a hospital tank.

Where can I buy treatment medications?

Browse Fast Aquatics treatment products with carrier-tracked Buyer Protection.

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