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Skin Flukes

Gyrodactylus

High severity ⚠️ Contagious

microscopic skin worms that cause flashing, excess slime and skin irritation, treated with praziquantel

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Symptoms

Catching illness early gives the best chance of recovery, so check your fish daily. Flashing and rubbing, excess slime, clamped fins, reddened or irritated skin and lethargy; unlike gill flukes the irritation is mainly on the body. Act promptly if you see several signs together.

Causes

Microscopic parasitic worms (monogeneans) that live on the skin, introduced with new fish or plants and multiplying on stressed fish in poor water. The underlying trigger is almost always stress, poor water quality or a newly introduced animal.

Treatment

Treat with a praziquantel-based anti-fluke medication for the full course, improve water quality, and quarantine affected fish. Repeat dosing as directed to catch newly hatched parasites.

While treating, increase aeration, remove activated carbon from the filter, finish the full course even after symptoms fade, and keep the water immaculate. Marine treatments belong in a separate quarantine tank, never the reef.

Prevention

Quarantine new fish and plants, and keep water clean and stable to deny these parasites a foothold. The golden rules: quarantine new arrivals, never overstock or overfeed, avoid sudden swings, and keep up regular water changes.

FAQ

What is Skin Flukes in fish?
Microscopic skin worms that cause flashing, excess slime and skin irritation, treated with praziquantel.
How serious is Skin Flukes?
It is rated high severity and is contagious, so treat the whole system promptly.
How do I treat Skin Flukes?
Improve water quality first, then use the correct treatment for the cause (see the Treatment section), removing carbon while medicating and completing the full course.
Can Skin Flukes be prevented?
Yes - quarantine new arrivals, keep water pristine and stable, and avoid stress, which is what lets most diseases take hold.
Will it spread to my other fish?
Yes, it is contagious - treat the whole tank/system, not just the visibly affected fish.

This information is general guidance, not veterinary advice. Consult an aquatic vet for serious cases.

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