Anchor worms: These are straight worm like attachments to a fish's body. They are a parasite that will drain the fish. How to treat Anchor worm.
Bacterial Infections in fish: Sluggishness, faded color, frayed fins, bloating, cloudy eyes, sores, abscesses, red streaks on body, reddening or inflammation of the skin or the fins, bulging eyes, rapid breathing are all signs that may indicate a bacterial Infection. Treat with an antibiotic. If one anti-biotic fails try a different type of antibiotic. There are 2 types gram positive and gram negative.
Blood parasites in fish: These are single-celled organisms that have infected the fish's blood. They are not directly transmitted from fish to fish but require an intermediate host such as snails or leeches. When the only symptoms are listnessness and weight loss then it might be blood parasites. Treat by killing off all snails, leeches and any other invertebrates.
Bloody Fins: Sign of red pest ( fish septicemia ) and is usually caused by an internal bacterial infection. Best cured with food dosed with an antibiotic. Remember to try two or three alternative antibiotics.
Cotton wool disease: This is a bacterial infection that looks like fungus on the mouth, body or fins. More detailed description and treatment here.
Developmental problems and hereditary disorders: Development problems are caused by environmental factors that harm the normal development of fish. Hereditary disorders are where genetic harm or mutation occurs.
Dropsy: Recognised by bloating not caused by overfeeding or female laden with eggs, with scales that stick out. It is difficult to treat and contagious. Treat with antibiotics in the food. Diagnose and treat dropsy.
Fin Rot: Fin Rot is a bacteria that attacks the fins. This bacteria is usually the result of environmental stress such as poor water quality or bullying by other fish. Best treated with a dose of aquarium salt and bactericide from your local aquarist.
Fish pox: This is when the fish has raspberry like growths on the skin or fins. Treatment for fish pox.
Fungus on fish: Cotton-wool like tufts hanging on fish's body or fins. Causes loss of appetite and lethargy. Easily treated with antifungal medicines. Don't confuse this with cotton-wool disease. More detailed information and treatment here.
Gill disease: This is a range of diseases that have harmed the gills causing heavy breathing in the fish. Diagnose and treat gill disease.
Hole in the head disease : This is a disease that affects mostly cichlids and gouramis. It is most common in discus, angelfish, oscars, dwarf gouramis and blue gouramis. It is recognised by small holes in the skin around the head having a whitish grey discolouration. Detailed article here.
Ich: Fish has little white specks all over her body like measles but white. Fish itch and scratching against objects. It is highly contagious, but easy to cure. Raise the temperature to 84F or over and dose tank with Malachite green or Copper salts. Maintain dose for 14 days.
Internal parasites in fish: Appetite dwindles, belly swells, faeces thin and stringy. Feed with antiparasitic food
Lymphocystis: This is a viral infection and can be recognised by berry like growths on the skin. There is no effective treatment except by quarantining the other fish away from the infected fish. The tank needs to be thoroughly sterilised before using again.
Mouth fungus: This is cotton wool disease but around the mouth area.
Nutritional deficiency in fish: This only occurs in fish that live in aquaria. It occurs because the fish are fed the wrong type or quantity of food. This leads to vitamin, mineral, protein, or carbohydrate deficiency in the fish resulting in ill health. More about nutritional deficiency here.
Pop-Eye: Usually sign of a bacterial infection. Fish antibiotic medication will usually cure this. Perhaps a second does with a different antibiotic will do the trick. However check for other symptoms as pop eye is usually a symptom and not a disease. Some parasitic infections cause pop eye too.
Tuberculosis - fish variety: Sluggish behaviour, loss of color, no appetite, weight loss and skin defects are signs of fish TB. Treat with sulphafurazole, doxycycline, minocycline or erythromycin . Also be careful because it is possible for people to be infected through broken skin.
Velvet: Symptoms include scratching, clamped fins, small gold to grey white peppery spots, loss of color, weight loss, and fast breathing. Cure with parisitic medication. For more detailed explanation of velvet.
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