Common Fish Diseases


4 May 2007
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Whitespot - Cryptocaryon irritans

flicking and scratching against various surfaces, small (1mm) white spots covering fins and body.

Comments: this is a highly infectious disease that spreads rapidly and may need an equally rapid medicinal response.


Black Spot

small (1mm) black spots on the body. Fish will flick and scratch.

Comments: spots are not usually so numerous as those connected with whitespot, neither are they so deadly. Surgeonfish seem to be particularly vulnerable.


Gill and Fin Flukes

Symptoms:Flicking and scratching against rocks and other surfaces, rapid breathing, cloudy eyes, white patches on body, worm-like parasites sometimes visible but not always.

Comments: This is another disease that is highly infectious and can be fatal if not treated quickly. It is caused by small worm-like parasites. They multiply quickly and can clog the gill of the fish causing slow suffocation.

* no pic


Symptoms: Erosion of fins and fin rays, reddened areas, lethargy, poor appetite.

Comments: This disease is usually associated with stress, sometimes brought on by poor water quality. Healthy animals can usually resist infections. Finrot usually begins as a mild external infection causing a reddening of the base of the fins. In severe cases, the animal's body and mouth may be eaten away.


Head and Lateral Line Erosion - HLLE

Symptoms: Erosion of the lateral line and the formation of pits in the skin.

Comments: This disease is usually caused by poor environmental conditions and poor water quality. If conditions are not improved, the condition of the fish will slowly deteriorate and the animal may die.

Cauliflower Disease - Lymphocystis

Symptoms: Small warty clumps on the fins or body that resemble small cauliflowers.

Comments: This disease is caused by a virus and often looks worse than it is. It is rarely fatal and will usually clear up on its own if optimum water quality is maintained.

Treatment: There is no effective treatment for this disease. A short freshwater dip may help. Maintain optimum water quality and symptoms should improve with time. If a secondary bacterial infection should occur, move the animal to a hospital tank and treat with antibiotics.

We have a Copperbanded Butterfly in quarantine for a week. It is eating bloodworm and aiptasia. But it is flashing the rhs and damaging the scales.
Here is a pic of the rhs, note the hook. Can anyone help identify? And suggest treatments. Thanks.
Tom plz look after the okie...mine has a single pin head size white dot on the tail fin, i hope the cleaner wrasse takes care of it.
my clown has developed loads of small black dots on its pectorial and anal fins and even on his head.Still looks healthy and strong but i am very conserned,what to do HELP
I'm sitting with a clown thats got anchor worm... not sure how to fix it... for those that dont know anchor worms are parasitic Copepods...
further to the above post.... in FW tanks you would use a copper based treatment... obviously not an option in a reef tank....
Treat it in a quarantine tank :)

Otherwise, clowns are a dime a dozen, throw the sick one away and buy a new one :p
Viper you wanna come catch him? i'll fly you down to cpt :p

its not really doing anything negative to him/it... its just a parasite that sits on the skin sucking blood....
i was wondering if anyone can help me. ive got a black google eye fish, ive had it for 2 weeks now and it looks like his fin on his back has been eaten away, or something like that. there is a funny looking thing on its back, i looks like a paresite. its seethrough with a little dot in the middle. what is it?
im not sure what the proper name is, it looks almost like a gold fish but its black and has these big bulging eyes
hey guys, my brother has a pair of allardi clowns.
we did a swop over from a boyu to a better nano tank (tobes nano tank)
and in the process both of these clowns have broken out in tons tiny white spots.

my question is:
which way is best to treat them,
medically with myxazin?
or with a fresh water dip?
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