The Fish Guru

Keeping Your Guppies Healthy: A Guide to Common Diseases

Guppies are one of the most popular aquarium fish known for their vibrant colors and small size. However, their vulnerability to diseases is a major concern for every fish keeper.

Maintaining a clean and healthy aquarium environment is essential, but even the most diligent fish keepers may still find themselves dealing with common guppy diseases at some point. This article aims to provide an informative guide on these diseases and their causes, symptoms, as well as effective treatments to avoid losing your beloved guppies.

1. White Spot Disease/Ich

Ichthyophthirius multifiliis, commonly known as Ich, is a parasitic infection that affects both freshwater and marine fish.

The disease spreads quickly, especially in poor water quality conditions rich in nitrite, nitrate, and ammonia. Symptoms include the appearance of white spots on the guppy’s body and fins, as well as behavioral changes like hiding, rubbing against objects or plants, and gasping for air at the water’s surface.

An effective cure involves treating the water with medication that can eradicate the parasite while maintaining the aquarium’s water quality.


Fin and Tail Rot

Fin and tail rot are caused by microbial infections resulting from poor water quality, especially high levels of nitrite, nitrate, and ammonia. The disease can also be caused by physical damage to the fish’s fins or tail, which results in bacterial infections.

Symptoms include frayed fins, inflammation, and white or red edges on fins and tails. The most effective treatment involves removing the infected fish from the aquarium into a quarantine tank for medication while improving the aquarium’s water quality conditions.

3. Swim Bladder Disorder

Swim Bladder Disorder affects the gas-filled sac located in a fish’s abdomen, which enables them to control their buoyancy.

Poor feeding habits, constipation, and biological abnormalities are some of the leading causes of swim bladder disorder. Symptoms include swimming difficulty, abnormal swimming positions, and floating or sinking to the bottom.

Treatment involves fasting the fish for a few days, reducing their feeding portion, and providing a blended diet packed with fiber-rich and digestible food that will help regulate digestion. 4.

Columnaris & Mouth Fungus

Flexibacter columnaris is a bacterial infection that causes columnaris, and Saprolegnia, known as fungal pathogen, causes Mouth Fungus. The bacteria and the fungus thrive in poorly maintained and filthy water conditions, particularly in fish that are under stress.

Symptoms include fuzzy white growth around the mouth and fins while columnaris appears as white or yellow patches on the fish’s skin. The effective cure for columnaris and mouth fungus is isolation and treatment in a quarantine tank with medication while bettering the primary aquarium’s water quality conditions.

5. Velvet (Oodinium)

Oodinium pilularis is a parasitic illness that primarily affects freshwater fish under high temperatures and poor water quality.

Symptoms include a yellow to rusty coating on the fish’s body with behavioral changes like hiding, gasping for air at the water surface, and clamped fins. Treatment includes isolating the infected fish and treating with medication while enhancing the aquarium’s water conditions.

6. Popped Eyes (Popeye)

Popeye is a bacterial infection that causes swelling and bulge of the fish’s eyes from the socket.

The causes of Popeye include physical trauma, which damages the eye socket’s tissues, dietary imbalances, and contaminated water by pollutants. The symptoms are visible as bulging eyes, difficulty swimming, and often cloudy corneas.

Treatment involves regular water changes with antibiotics, improving water quality, and quarantining infected fish.


Red Blood Spot

Red Blood Spot is a severe hemorrhagic septicemia caused by a gram-negative microorganism, Aeromonas hydrophila, that targets fish with high stress and poor living conditions. The symptoms show through red spots on the fish’s body and fins, and the fish’s lethargy and refusal to feed.

The most effective treatment of Red Blood Spot involves proper water changes, high-quality feed, the use of bactericidal medication, and isolation in quarantine tanks with tailored medication. 8.

Camallanus Worm

Camallanus cotti is a nematode worm that affects fish in poorly maintained and overstocked aquariums. The cause of Camallanus Worm includes fish overfeeding and poor water changes.

Symptoms include the presence of red worms protruding from the infected fish’s anus, lethargy, and lack of appetite. Treatment includes isolation in a quarantine tank and medication, following the veterinarian’s advice.

9. Viral Hemorrhagic Septicemia (VHS)

Viral Hemorrhagic Septicemia is a life-threatening illness that spreads extremely fast, especially through contaminated water and vulnerable fish.

The symptoms include head swelling, bulging eyes, skin hemorrhage, and breathing difficulty. The most effective treatment involves isolating the infected fish immediately, promptly consulting the veterinarian while providing a fish-friendly and healthy environment in quarantine.

10. Scoliosis (Bent Spine)

Guppy Scoliosis is a hereditary condition that can be affected by the surroundings and harsh tank conditions, including a lack of calcium and vitamin D3.

The symptoms include bent spines or curved tails with deformities. Treatment involves improving water conditions, avoiding overstocking, and providing a well-balanced and suitable diet.

11. Fish Tuberculosis

Fish Tuberculosis is a bacterial infection caused by Mycobacterium organisms, which spreads through poor water conditions or from infected wild fish.

The symptoms include weight loss, lethargy, eye clouding, fin rot, and loss of appetite. Treatment of Fish Tuberculosis involves isolation in quarantine, prescribed medication as advised by the veterinarian, and improvement of primary aquarium conditions.

12. Hexamitiasis

Hexamitiasis is a pathogenic illness caused by Hexamita that spreads in poorly maintained and overpopulated aquariums.

Symptoms include loss of appetite, weight loss, and the presence of whitish fecal matter. The most effective treatment involves removing the infected fish from the aquarium and isolating them in quarantine with medication while improving water conditions.

13. Gill Flukes

Gill Flukes is a parasitic illness caused by pathogenic flatworms that affect fish gills in contaminated water.

The symptoms of Gill Flukes include rapid breathing, lethargy, and weight loss. An effective cure involves isolation in quarantine tanks and treating with medications and improving aquarium water conditions.


Protecting your guppies from common diseases requires regular aquarium maintenance, monitoring the water quality, providing a proper diet, and knowing the signs and symptoms of potential diseases. With proper care, attention, and the right treatment methods, your guppies can live in a healthy and safe aquarium environment.

Remember to maintain good hygiene and avoid overcrowding while consulting with your veterinarian regularly to avoid any health threats to your guppies. Overall, this article has provided an informative guide on common guppy diseases, including their causes, symptoms, and treatments.

It is crucial to maintain a clean and healthy aquarium environment to reduce the risk of guppy diseases. Regular monitoring of water quality, providing a proper diet, and consulting with a veterinarian when necessary can help keep our beloved guppies healthy and safe.

Remember to take note of the symptoms, isolate and treat infected fish with medication while improving water quality conditions. With the right care, your guppies can live a long and healthy life in your home aquarium.

Popular Posts