FastAquatics
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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Aquarium-keeping fundamentals

Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.

Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.

Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.

Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.

Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.

Frequently asked questions

How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.

What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.

How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.

Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.

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