Fin Rot

Fin Rot is a bacteria that attacks the fins and in extreme cases, the body. This bacteria is usually the result of environmental stress such as poor water quality, bullying, etc. Part of treating this illness is early detection. If left untreated, secondary infections can occur. Fin or tail rot can also be a secondary infection caused by stress from other diseases. There are many different ways that harmful bacteria can enter your aquarium, some fish at the pet store will look perfectly normal but harbor harmful bacteria that the fish has become immune to, and will release the bacteria through its feces in your tank. However, healthy fish will be able to fight off the bacteria with little trouble. If only a few fish infected, it is best to move them from the main tank, and place them in a bare hospital tank for treatment, but in most cases a hospital tank is not an accessible. Fish should never be given low dosages of medications over a long period of time, this could cause the bacteria to become immune to medications. Always follow the instructions on the bottle.

Symptoms: Rotting fins, loss of appetite, sluggish movements and laying on the tank bottom.

Treatment: There are numerous treatments available at any fish/pet store.

Body Fungus

Body Fungus is just that, fungus. It will attack your fish's skin and cause ulcers or death in extreme cases. Large amounts of organic materials such as decaying food or fish waste can cause a breakout of fungus in your aquarium. Open wounds can develop fungus. The fungi feeds by excreting digestive enzymes which if it’s on the fish, slowly digests parts of the fish. Though cured easily, if the fish doesn't get prompt treatment it will surely die. Secondary infections are also common.

Symptoms: White or grayish patches appear on the skin or gills that look like cotton or wool.

Treatment: Either purchase a treatment from your local fish/pet store specifically for fungus or buy an all round antibacterial treatment such as Melafix.

Skin & Gill Flukes
Flukes are a parasite that attack the gills and skin of infected fish. Small numbers of flukes are pretty much harmless, but in bad water conditions, over crowding, or aquaria with high organic content, they can multiply at a fast rate. According to the fish doctor the only reliable way to diagnose is with a skin scrape.

Symptoms: Fish will flash or scrape its self against aquarium décor, rapid gill movement, at a more advanced stage, the fish will isolate its self and lie at the bottom with fins clamped. Also cloudy skin due to excess mucus.

Treatment: Flukes are hard to treat and complete eradication is virtually impossible. It is said that for individuals affected with flukes, consecutive salt baths over 2-3 days can be useful. There are commercial treatments avalible.

Hole In The Head – Hexamita
Hole in head is a very serious disease that warrants prompt treatment. Large cichlids such as Oscars, discus, and pikes are very susceptible to this disease. Hole in head, believe it or not, is an intestinal tract infection.

Symptoms: Holes in the head area, ulcerations on the body, loss of appetite

Treatment: A recommended treatment is Hex-A-Ex, although I am not speaking from personal experience. Contact your local fish/pet store or the forum for more info.

White Spot - Ichthyophthirius (Ich)
Ich attacks the skin and gills of the infected fish. Ich is a parasitic infestation that is a very common pest among hobby aquarists. It can be introduced by rapid changes in water chemistry such as temperature or ph (these weaken the fishes immune system leaving them susceptible to disease), poor water quality, or bullied fish. Ich is easily treated if caught in time. Once symptoms are observed, treatment must be swift. The life cycle of ich is about 4 days, if treated, it will have to be a minimum of 4 days. While the ich is in cyst form, it cant be killed by medication so you have to treat long enough for the cysts to hatch into its free swimming form.

Symptoms: Fish will flash or scrape its self against aquarium décor, appearance of small white cysts or "sprinkles of salt" on the body or fins, loss of appetite, rapid gill fluctuation (breathing heavily), exhaustion, isolation, fish may hang out near the surface or water return.

Treatment: There are many different treatments available for ich, just goto any fish/pet store. Many people believe that the addition of aquarium salt at the ratio of 1 tablespoon per 5 gallons of water, to be very effective along with the commercial treatment, and upping the temperature to 82F.

Pop Eye
Pop eye is an infection that can have a few causes such as bacteria, Poor water quality, injury, poor nutrition, tumors, vitamin deficiently. The symptoms are quite clear.

Symptoms: Eye or eyes protrude from head, cloudy eyes from bacteria infection.

Treatment: Generally hard to treat, u may try a broad spectrum antibiotic.