viral · both tank

Lymphocystis (cauliflower disease)

Lymphocystis is a viral disease that causes cauliflower-like white or pink lumps on fish skin + fins. Self-limiting in healthy fish; primarily a cosmetic issue.

Reviewed by Fast Aquatics husbandry team · Updated May 2026
Severity: Cosmetic - rarely fatal

Symptoms

What causes it

Lymphocystis virus, usually contracted from another infected fish or stress.

Treatment options

Always treat in a separate quarantine tank.

No treatment needed. In most cases, lymphocystis self-resolves within 4-8 weeks. Maintain pristine water + low stress.
Manual removal. For severe lesions: small ones can be carefully scraped off (only if you can hold the fish safely).

Prevention

Reduce stress. Quarantine new fish. Pristine water quality supports immune response.

Frequently asked questions

What does Lymphocystis (cauliflower disease) look like?

White or pink cauliflower-like lumps on skin or fin edges. Slow-growing, painless to fish. No behavior change.

What causes Lymphocystis (cauliflower disease)?

Lymphocystis virus, usually contracted from another infected fish or stress.

How is Lymphocystis (cauliflower disease) treated?

No treatment needed: In most cases, lymphocystis self-resolves within 4-8 weeks. Maintain pristine water + low stress.

Can Lymphocystis (cauliflower disease) be prevented?

Reduce stress. Quarantine new fish. Pristine water quality supports immune response.

How fatal is Lymphocystis (cauliflower disease)?

Cosmetic - rarely fatal

Related

Browse the full disease database for 45 aquarium conditions with treatment protocols, or check the care library for prevention-focused husbandry guides. Use our symptom matcher to rank likely diseases from observed signs, the water parameter checker to diagnose related water-quality issues, or the QT timeline calculator to plan a treatment schedule.