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FISH / health & care

Is My Fish Sick?

Troubleshoot fishy health problems

Overview

What’s wrong with my fish?

The chart below can help identify fish health symptoms and how to help:

Symptoms
Disease
Treatment
Prevention
Tattered fins, tail. Skin sores. Swollen abdomen. Bulging eyes. Red fins, skin
Bacterial infection (Aeromonas, Pseudomonas)
Isolate sick fish. Add antibiotics to the water and use antibiotic-medicated food.
Maintain good water quality. Quarantine any fish with signs of the disease.
Fuzzy spots on skin, mouth
Bacterial infection (Flavobacterium)
Isolate sick fish. Add antibiotics to the water and use antibiotic-medicated food.
Maintain good water quality. Quarantine any fish with signs of the disease.
Bumpy growths on skin, fins
Carp Pox
Treat affected areas with topical disinfectants. Add Formalin solution to water.
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank. Use anti-bacteria-medicated fish food.
White “pimples” on skin, fins
Viral infection (Lymphocystis)
Treat affected areas with topical disinfectant. Add Formalin solution to water.
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank. Avoid contaminated live food; use anti-bacteria-medicated fish food.
Cotton-like “hair” on fish, eggs, uneaten food
Water Mold
Treat water with Methylene Blue, Acriflavine, Victoria Green or Malachite Green.
Handle fish gently to avoid injuring skin; avoid overcrowding; keep temperature stable and water clean.
Increased gill movements. Fins clamped to sides. Lying on bottom of tank. White or grayish “slime” on skin
Parasites (Costia, Chilodonella, Trichodina, Epistylus)
Treat water with Formalin, Malachite Green, Acriflavine or copper sulfate
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
White speckles on body, fins. Scraping body against rocks
Ich (known as freshwater white spot disease)
Treat water with Formalin, Malachite Green, Acriflavine or copper sulfate
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Golden speckles on skin
Velvet Disease
Treat water with copper sulfate
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Spots on top of head, back
Hole-In-the-Head Disease
Feed fish food containing Metronidazole
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Protruding worms. Poor growth. Weight loss
Camallanus Worms. Capillaria Worms
Add Levamisole to food. Feed an anti-parasite medicated food.
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank. Avoid contaminated live food.
Inflamed gills. Excess mucus on skin. Scraping body against rocks
Gill Flukes. Skin Flukes
Add Praziquantel to water. Feed an anti-parasite-medicated food.
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Gray to white wormlike parasites on skin
Anchor Worms
Remove visible parasites with tweezers. Add Dimilin or Trichlorfon to water.
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Small, moving specks on fish, in water
Fish Lice
Add Dimilin or Trichlorfon to water
When adding new fish, do not add the water they came in. Quarantine new fish in a separate tank.
Rapid gill movements. Rises to surface to gulp air
Lack of oxygen
Turn on filter, change water
Keep filter running; use air stone and pump.
Rapid gill movements. Inflamed gills. Mucus on skin. Fins clamped to sides. Lying on bottom of tank. Rapid death of multiple fish
Poor water quality
Treat water with ammonia remover, aquarium salt or other appropriate water-quality-improvement product.
Test water quality frequently; change water regularly; aerate and filter properly.

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