Disease + treatment guide

Bryopsis Algae

Bryopsis Algae guide for aquarists. Symptoms, treatment protocol, prevention, and when to escalate.

Bryopsis Algae TL;DR

Affects: reef tanks · Symptoms: feathery green hair algae taking over rockwork

Treatment: Fluconazole 14-21 days, magnesium spike, manual removal

What is bryopsis algae

Bryopsis Algae is a common aquarium disease/pest affecting reef tanks. Recognizing it early and treating quickly is the difference between losing a single fish and losing an entire tank.

Symptoms to watch for

feathery green hair algae taking over rockwork. 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

Fluconazole 14-21 days, magnesium spike, manual removal. 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.

Bryopsis Algae FAQ

Is bryopsis algae contagious?

Pests can spread between corals; isolate infested specimens immediately.

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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