When fish are sick, they deviate from their normal behavior like every other living being on being sick. You can sense their sickness by a close observation of their aberration from their routine behavior. Fish tend to lose their appetite, become lethargic, restless and even indulge in aggressive fighting and scratching against stones and decorative objects in water tank.

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You should take care in every possible way to ensure that your fish remains healthy and fit. This may range from providing proper hygiene and medication to best quality tank water and environment conditions. So, here are some of the commonly occurring diseases in fish.

Turning Black

Symptoms And Problems

The common symptoms of this ailment are that the skin comes off in patches and become dark, in initial stages small white patches may appear all over the body and this is seen in newly placed fish in the aquarium.

Treatment

  • Treat fish tank with potassium permanganate.
  • Change the water in the aquarium daily.
  • Remove all decorations in the tank.
  • Use of Antihistamines.
  • Improvisation of water quality.
  • Use filtered and oxygenated water.
  • Remove and replace 50 percent of the water in the tank with fresh, non-chlorinated water.
  • Contact a veterinarian for assistance if the condition does not improve.

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Tumor

Symptoms And Problems

The common symptoms of this ailment are that in internal tumors, swelling or distention may occur while in external tumors, growing on skin occurs that may cause problem in feeding and results in an unattractive fish.

Treatment

  • Usually incurable.
  • Consult a veterinarian about potassium iodide treatment for thyroid tumors.
  • Removing tumors surgically.

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Fin Rot

Symptoms And Problems

The common symptoms of this ailment are rotting and decaying fins, black/brown fin edges, fray fins, inflamed base of fins, white dots on fins.

Milky white areas appear in the fins or tail, particularly around the edges that results in fish laying on the bottom of the tank.

Treatment

  • Tetracycline medication.
  • Remove any carbon filtration before using medication because the carbon will absorb the medication.
  • Use OTC antibiotic for fin or tail rot.
  • Apply Chloramphenicol.
  • Treat with phenoxyethanol, malachite green methylene blue.
  • Use aquarium salt.
  • Use antifungal medication.
  • Feed fresh food.
  • Maintain water temperature.
  • Use anti-bacterial treatment such as antibiotics.

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Turning White

Symptoms And Problems

The common symptoms of this ailment are that skin comes off in white patches and become totally white with some behavioral problems in fish.

Treatment

  • Change of filter media.
  • Use a commercially prepared water de-chlorinator.
  • Maintain constant and appropriate temperature.

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Constipated

Symptoms And Problems

The common symptoms of this ailment are swelling of the body and abdomen that results in loss of appetite and disturbed eating habits, refusing all food.

Treatment

  • Improve diet and maintain dietary requirements.
  • Give a varied diet suitable for the fish.
  • Feed fish dried food soaked in glycerol, castor oil or medicinal paraffin oil.
  • Make fish food that includes anti-parasite ingredients.
  • Feed easily digested foods.
  • Select food for fish as per natural wild habits of fish.

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White spots on

Symptoms And Problems

The common symptoms of this ailment are small white spots on the fins and on the body and it looks as if fish have salt all over it. Other symptoms to note are outer layer of fish skin gets thickened, rapid breathing occurs with excessive mucus on skin and irritation occurs that sets gill movement.

All these symptoms results in a lethargic fish hiding abnormally, resting on the bottom and rubbing and scratching against objects.

Treatment

  • Increase temperature of water to 82 degrees Fahrenheit.
  • Remove any carbon filtration before using medication because the carbon will absorb the medication.
  • 50% water change of the tank.
  • Treat for the recommended amount of time.
  • Use treatment like AquaPlus or Stress Coat when adding new fish or completing water changes.
  • Add aquarium salt.
  • Chemical treatments.

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Tail Missing

Symptoms And Problems

The common symptoms of this ailment are ripped fins or tails, a clean split or a bite-size piece missing that is quite painful to fish.

Treatment

  • No Physical Damage to fish should be ignored.
  • Place fish in separate tank, which are aggressive to each other.
  • Maintain quality of water changes and feed.
  • Treat with antibiotics or aquarium salt.

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Losing Scales

Symptoms And Problems

The common symptoms of this ailment are that fish will knock out their own scales by “flashing”

Treatment

  • Stabilize the pH.
  • Optimize pH, the Ammonia, Nitrite and Nitrate.
  • Use Fish Tank Test Kit to check levels
  • Use injections of antibiotics.
  • Feeding medicated foods called MediKoi.

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Swim Bladder Disease

Symptoms And Problems

The common symptoms of this ailment are erratic Swimming Position, loss of equilibrium, unable to maintain buoyancy and fish may hang in the water due to their disturbed balance.

Treatment

  • Stop feeding the fish for a few days.
  • Apply Chloramphenicol.

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Red Spots

Symptoms And Problems

The common symptoms of this ailment are mobile red spots and red spots reach irritation point.

Treatment

  • Place fish in backyard pond
  • Use just enough water to keep the fish afloat.
  • Physical removal of parasite.
  • Treatment with trichlorfon-based chemical.
  • Regular water changes.
  • Try a malachite green and formalin mixture.

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White Spots on Tail

Symptoms And Problems

The common symptoms of this ailment are fins folded against the body, scratching decorative objects and disordered swimming.

Treatment

  • Apply Malachite green dye.
  • Anti-parasitic medicines.
  • Optimize levels of pH and temperature.
  • Boiling decorative objects to disinfect, before putting them into the aquarium.
  • Cleaning new plants with a strong disinfectant.

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Floating

Symptoms And Problems

The common symptoms of this ailment are floating listlessly, bobbing about at the surface and rolling upside down.

Treatment

  • Increase the water temperature.
  • Add salt to the water.
  • Antibacterial remedy.

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Lethargic

Symptoms And Problems

The common symptoms of this ailment are flashing movements and listlessness of fish.

Treatment

  • Regular water changes.
  • Move the fish to a separate bowl with fresh water.
  • Use de-chlorinated tap water.
  • Treat with a medicine called Pimafix.
  • Maintain excellent water quality.
  • Only one person should feeding the fish.

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Common Diseases

Symptoms And Problems

The common symptoms of this ailment are grayish white marks, unhealthy fish, various types of spots, behavioral changes, physical effect, irritated fish, swimming in hurry, and flapping fins very fast.

Treatment

  • Anti-bacterial medications.
  • Improve water quality.
  • Anti-fungal medications.
  • Treat with antibiotics.

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Fungus Treatment

Symptoms And Problems

The common symptoms of this ailment are appearance of cotton wool like growths, observable skin and gill lesions, gray or white patches on the skin/gills, the fish may become sluggish, lose balance and eventually show external cysts or sores and cotton wool like appearance growth on the skin, mouth, fins or gills.

Treatment

  • Remove the affected fish to a quarantine tank or treat the whole aquarium
  • Treat with aquarium salt.
  • Treat with an antifungal agent.
  • Maintain a clean tank – remove any decomposing material immediately.
  • Avoid erratic feeding.
  • Ensure good pond sanitation
  • 1% Phenoxethol solution added to food or Chloromycetin added to the food.

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Eye Problems

Symptoms And Problems

The common symptoms of this ailment are opaque eye lens, cloudy eyes, pop eye and heavy infestation resulting in blindness.

Treatment

  • Remove or cull infected fish.
  • Move to a recuperation tank with antibiotics in case of physical injury to eye.
  • Add tetracycline, chloromycetin (chloramphenicol) or another antibiotic.
  • Dim the lighting and improve diet.
  • Improved diet with vitamin A.
  • Penicillin or amoxicillin.
  • Improve diet and include a lot of vitamins.

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Swim Bladder In

Symptoms And Problems

The common symptoms of this ailment are difficulty in regulating buoyancy, fish laying on the bottom of the tank, floating on the surface where it seems as if the fish are drunk having trouble keeping its balance and constipation.

Treatment

  • An improved diet can often help the fish recover.
  • Use chemical medications.
  • Give preferred environment.

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Stunted

Symptoms And Problems

The common symptoms of this ailment are that fish stop growing in size that is below the normal size and therefore, despite the overall size of the fish not getting bigger, the organs will actually still continue to grow and enlarge.

Treatment

  • No exposure to stress.
  • Appropriate feeding regime.
  • Give proper nutrition.
  • Limit overcrowding.

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Blackspots

Symptoms And Problems

The common symptoms of this ailment are small dark spots on fins and body, small black speckles on body, flickering, small black smudges on fish, scratching against surfaces.

Young fish have growth problems if heavily infected and thus they become very irritated.

Treatment

  • Commercially available treatments and preventatives.
  • OTC medication for parasites.

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Tubercles

Symptoms And Problems

The common symptoms of this ailment are raised white pimple-like growths on the head, pectoral fins and opercula, numerous nodules in the spleen, liver, kidney, heart, intestines, gills, muscles, sex glands, skin, eyes, and the skeleton. Fish become inert, hide in secluded places, move in violent rushes, stop feeding and swing on their side.

Treatment

  • Destroy affected fish.
  • Add kanamycin or rifampicin in the food.
  • Antibiotics should be added into the water.
  • Medicines like rifampicin, kanamycin, chloramine, chlorine solution, doxycycline, monocycline, oxytetracycline, and tetracycline.
  • Maintain a healthy environment.
  • Provide with a nutritionally balanced diet
  • Avoid overcrowding.
  • Maintain high water quality.

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Spine Curvature

Symptoms And Problems

The common symptoms of this ailment are curved or crooked spine skeletal deformity causing sluggish movement. Loss of appetite, discoloration and skin defects also observed.

Treatment

  • Remove infected fish.
  • Add salt and raise the temperature.
  • Treat with Penicillin ointment.

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Bloating

Symptoms And Problems

The common symptoms of this ailment are female is unable or unwilling to expel the eggs because of Intestinal blockage and fish swims inverted.

Treatment

  • Epsom Salt treatment or Antibiotic Treatment.
  • Change in diet is required including more variety and roughage.
  • Feed a shelled pea.
  • Feed a pea with a crystal of Epsom salts.
  • Remove activated carbon.
  • Increase aeration during treatment.
  • Use of a quarantine tank is suggested.

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Cysts

Symptoms And Problems

The common symptoms of this ailment varies greatly and they are pus-filled cysts under the skin which could be true tumors exuding pus and fluid having no effect on behavior at all but it hinders eating and may cause behavioral lethargy and malaise.

Treatment

  • Unknown, may be incurable if they turn out to be true tumors.
  • Different treatment options that can be attempted.

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Lumpy Body

Symptoms And Problems

The common symptoms of this ailment are that it manifest as growth occurring on the body surface where internal growths can also enlarge.

Some skin growths are of same color as surrounding skin. Many abnormal skin and fin growths are harmless, but some are potentially life-threatening.

Treatment

  • Permanently isolate the affected fish.
  • Assess overall aquarium/pond hygiene.
  • There is no chemical cure.
  • Fish’s immune system overpowers the virus, causing the lumps to disappear in time.

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Restlessness

Symptoms And Problems

The common symptoms of this ailment are increased respiration, open gills, loss of color, gasping for air which causes fish to appear restless.

Treatment

  • Aeration of the water.
  • Good balance of plants.
  • All decaying plant matter, foods and algae should be removed from the aquarium.
  • If the problem is serious, an immediate water change should be done. Adding fresh water will significantly increase oxygen levels.

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Color Dullness

Symptoms And Problems

The common symptoms of this ailment are that some fish change colors temporarily and becomes very dull. Fish results in different color or color dullness and sometimes are less active due to indigestion.

Treatment

  • Bright sunlight.
  • Keep fish tank in an area that is well-lit.
  • Keep tank clean.
  • Maintain nitrate and ammonia levels.
  • Regular treatment with a worming medication.
  • Careful handling of fish between the store and home.

Note: If the fading is not due to a health concern, unnecessary treatment could be harmful, too.Go to top

Step by Step Fish Killing/Culling

Symptoms And Problems

The common symptoms of this ailment are that fish generally lie at the bottom of the tank, doesn’t eat, and lose weight with folded or torn fins, gasping for air resulting in rapid breathing.

Treatment

  • Separate sick fish.
  • Maintain water quality.
  • Clean the tank and change the water.
  • Remove the filter and treat the water.
  • Treat the water with a heat and salt method.
  • Feed your fish veggies and low protein foods.

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Male Crowntail

Symptoms And Problems

The common symptoms of this ailment are unique tail fin characteristics, flashy fin extensions.

Some fish are shy and stressed while other are more outgoing. Male crowntails are very aggressive to other members. They have unique tail fin design and spikes looks prominent and give the tail fin a crown-like appearance.

Treatment

  • Don’t house your fish in anything smaller than a 1-gallon tank with a lid.
  • Ensure water temperature stays between 62 and 82 degrees Fahrenheit.
  • Do not use any type of aeration system.
  • Include a live plant in the tank.
  • Remove all food that your fish doesn’t finish during that time period.

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Anchor Worms

Symptoms: Difficulty in breathing, lethargy, red worms in wounds, fish rubbing itself

Treatment: Potassium permanganate, salt dip, formalin dip, 1-2 tablespoons of salt in aquarium.
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Body Flukes

Symptoms: Fish scratching itself, isolation, reddened skin, gills moving quickly

Treatment: potassium permanganate, Droncit, Fluketabs, FormalinGo to top

Clamped Fin

Symptoms: Fins are folded against the body, dull behavior

Treatment: Review water quality and conduct a water change
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Dropsy

Symptoms: Bacterial infections, Bloating, parasitic infections or liver dysfunction

Treatment: Adding aquarium salt, preventative care and changing water regularly
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Lice

Symptoms: White spots on the gills, scratching, lice use suckers to attach & pierce the skin

Treatment: physically removing the parasite and cleaning the wound with an antiseptic like iodine or using lice solve
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Fungus

Symptoms: Grey, whitish or cottony growth on the skin

Treatment: Tea tree oil or salt or using solution of fungicide and antibiotics
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Gill Mites

Symptoms: Gasping at the water’s surface or gill covers that are partially open

Treatment: medications using sterazin & octozin, or using antibiotics
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Hemorrhagic Septicemia

Symptoms: hemorrhaging of their internal organs, skin, and muscle ,reddish tints, bulging eyes, bloated abdomens

Treatment: using antibiotics and performing regular water changeGo to top

Ick

Symptoms: Scratching, rapid breathing, resting on the bottom or clamped fins

Treatment: quarantining new fish for two weeks and plants for 3-4 days in a separate tank and Consistent temperature and good water quality will help prevent infections.
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Ragged Tail Fin

Symptoms: ragged, frayed fins, edges of the fins are often discolored (sometimes lighter, sometimes darker)

Treatment: partial water change, add some freshwater aquarium salt to the tank
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Tail, Fin and Mouth Rot

Symptoms: Fins turn whitish and die back, Jagged Fins, fish is not eating

Treatment: check water quality and add some freshwater aquarium salt to the tank
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Diseases Free Tank Tips

Fish are prone to disease. A well maintained aquarium will never be a hub of diseases. Most of the diseases will come from a poorly maintained aquarium. Any harmful environment is bound to affect animals at the end of the day. Read More

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Last update on 2024-03-11 / Affiliate links / Images from Amazon Product Advertising API

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Written by Debra Hutchinson, founder of FishXperts