Fish Care

Fish that have bump on their head

fish that have bump on their head

Nuchal hump: This fish may look like it swam straight into a ledge and got the most terrifying bump ever, but that big bump on its head is actually a Nuchal hump, also known as a kok.

The formation of this forehead bulge is hormonally induced and the male cichlid swells at the time of mating. They are rarely seen on females of some species but are always smaller than the male bumps. Two explanations are given about the purpose of a Nuchal hump. (1) they are used for sexual recognition (2) as fat stores. Anyhow, now you know that if you see a cichlid with a swollen forehead, he’s probably feeling the urge to get down.

Flowerhorn Cichlids

Flowerhorn cichlids fish are known for their distinctively bulge of the head and their colour or kok is formally called a nuchal hump. They are very popular among Asian fish hobbyists. They are also kept by hobbyists in America, India and Europe. There is a ban on their import into Australia.

Bumped Parrot Fish

The bumphead is the largest parrotfish in the world and the largest of all reef fish.

The parrot fish uses its parrot-like beak to scrape off algae from rocks and dead coral; Grind the inedible calcium carbonate (the rock material composed mostly of coral skeletons), which is released back into the rock as sand.

Bumphead parrot usually have a big protusion on their foreahead which resembles a pair of horns on a sheep.

The largest males have the largest bumps and sometimes use them as battering rams around spawning time, smashing heads into rivals in an effort to show their dominance and maintain territorial and breeding rights.

Bumphead parrotfish were most commonly found in red sea, western pacific and indian ocean. However, there has been a very sharp decline in these fishes which they are now protected only in specific places.

Bumpheads have certain traits that make them particularly vulnerable to overfishing, which has led to local disappearances in many parts of their range. Bumped parrotfish can live up to 40 years of age, they do not reach maturity until 5–8 years of age, and are likely to have low natural mortality as adults.

Bumpy head

For a bumpy head, fish known as bolbomaptopon muricatum the giant bumphead fish which is 4 feet in length and weighs up to 46 kg in weight known for its bumpy head. Its whimsical look gets a boost from pouty lips and yellow to pale face.

Different foreheads

A female Bolbomatophone (lower fish) and a male (upper), reflecting the differences between the sexes in forehead and size; The female’s forehead is tilted caudal towards the beak, but in males it is almost parallel to the beak. The males are usually larger than the females.

Lumps and bumps on tropical fish

There are also a number of diseases that cause bump on fish head;

  1. Lymphocystis
  2. Ulcer disease caused by aeromonas or pseudomonas
  3. Fish pox
  4. HITH or LLE with various causes and treatments
  5. Costia – a parasite that almost always causes small red hemorrhages, especially under the chin
  6. Various bacteria Diseases such as Colmaneris,
  7. Neoplasm formation.

The bumps that appear suddenly are usually a bacterial infection. If the disease process is caused by bacteria, it usually heals very quickly by rupture (like a boil). The white fluid that comes out is the pus that forms when white blood cells (immune cells) die, killing bacteria (normally).

Never try to break or squeeze the lump. Like a boil in humans, squeezing pus into the fish’s bloodstream can have fatal consequences. It’s also not a good idea to seal a drainage wound until the bleeding stops. The most common bacteria that cause this type of lump are Columnaris or Aeromonas.

Wound that are white at the edges and red in the center are usually aeromonas. Those that are red on the sides and white in the middle are usually columnaris. Both are gram negative bacteria.

The best treatment for this is any sulfa antibiotic that contains trimetheprim. It can be put in water and mixed with food – if you find Roomet B, use it.

Some research indicates that certain carbon filter materials may predispose fish to this disease, although the mechanism has not been determined. Better nutrition (provide a calcium/phosphorus/vitamin D supplement), less crowding, more water changes may help.

White bumps on fish almost always indicate illness or injury, although sometimes the bumps are completely normal, but it’s advisable to quarantine the fish with bumps from other fish to avoid infecting others.

Stress plays a factor in fish with bump on the head which can be as a result of fighting with other fishes or scraping against sharp objects such as tank decorations.

Removing the stress factors goes a long way in reducing the chances of diseases.


Any other ‘bumps’ and ‘lumps’ can be treated with a bath of potassium permanganate. You can often get it at your local pharmacy. Notes on the use of potassium permanganate. 1 drop stock pp is equal to 2 ppm per gallon. PP is usually used for 3 days, or 4 treatments every other day.

Do 20-30% water change before adding a second dose, if the water does not clear. After adding PP, watch for at least 15 minutes to make sure there are no adverse reactions. Then turn off the lights or cover the tank. Some of the water seems to rapidly deactivate the PP. It should be pink when you apply it and stay pink for at least 4 hours to be effective.

Do not use near eyes, mouth or gills. Use as a one-time application.

Note: Some water conditioners may inactivate certain medications. NovaAqua and PolyAqua will inactivate metals and quickly deactivate potassium permanganate.

If you follow combined Rally/Kanamycin treatment, use it according to package label directions, and add a single dose of Rally every 3-5 days.

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