LYMPHOCYSTIS

Technically, lymphocystis is classified as a viral infection that affects the cells of a pet fish. The most common symptom is large white growths on a fish’s body, sometimes being cauliflower-like in appearance. Though this is one of the few viral infections that can affect fish, it is relatively rare. There is no cure for lymphocystis, though isolation of infected fish usually results in remission of the disease.

DROPSY

Dropsy is a bacterial infection that can affect some pet fish. Dropsy is actually caused by a bacterial infection that affects a fish’s kidneys. The most common symptom of dropsy in pet fish is severe bloating of the body from fluid buildup, and renal failure. Protrusion of the scales is also seen in some advanced cases of dropsy. Since this is a bacterial infection, it can be treated by adding an antibiotic medication to a fish’s food. Some common antibiotics used to treat dropsy in pet fish include chloromycetin and tetracycline.

TAIL & FIN ROT

The condition most commonly known as “fin rot” is a bacterial infection that causes a ragged appearance of a fish’s tail and fins. This condition is most commonly caused by poor conditions in a fish’s tank, resulting in severe bacterial growth in the tank. Tail & fin rot can also be caused by aggressive behavior of certain types of fish, which may nip at the tail or fins of other fish in the tank. Tail & fin rot can also be caused by tuberculosis, in some cases. For treatment of tail & fin rot, antibiotics are the best course of action. Antibiotics can be added to the water of a fish’s tank, along with being added to a fish’s daily feeding portions.

TUBERCULOSIS

Tuberculosis in pet fish is caused by a bacterium called Mycobacterium piscium. The most common symptoms of tuberculosis in fish include lethargy, pale appearance, ‘hollow-belly’, visible skin ulcers, loss of appetite and loss of scales or fin tissue. The most common cause of tuberculosis in pet fish is overcrowding, or poor tank conditions. If a fish is living in a tank that has poor water quality, they become much more susceptible to developing tuberculosis. Certain species of fish are more prone to developing tuberculosis, as they are very sensitive to any changes to their environment. The most common treatment method used for tuberculosis in pet fish is treatment with Vitamin B-6 and Kanamycin for approximately thirty days.

SYMPTOMS

Identifying ich in pet fish is usually very simple, due to the visible symptoms of this condition. The primary symptom is the appearance of small white spots on a fish’s gills and body. In certain cases, these white spots may only be present in localized areas, such as around the gills. This disease is progressive, and as a fish becomes more uncomfortable, they may try to ‘itch’ their body by scraping against the sides of the tank. In more advanced cases of ich, a fish will develop respiratory distress, loss of appetite, severe agitation and eventual death.

RISK FACTORS

Though there is no dormant period with the Ich parasite infection, there are certain factors that may increase the likelihood that a fish will become infected with ich. Factors such as reduction of water quality, stress and changes in water temperature can all contribute to a fish becoming infected with the ich parasite. In addition to this, if a fish’s immune system is substantially repressed by infection with another health condition, this can also increase the likelihood that a fish will be infected with ich.

TREATMENT

Treatment for ich in fish is commonly supplemented with the raising of the tank’s temperature to 82-86 degrees fahrenheit. This temperature change should be done gradually, as to not upset the normal life cycle of the fish in the infected tank. This is usually combined with other treatment methods, such as chemical treatments. Examples of chemicals used to treat ich in pet fish include Quinine Sulfate, chelated copper, formalin, copper sulfate and malachite green. In some cases, diluted salts may be used to increase the salt level of a tank so that it is not a tolerable environment for the parasite that causes ich.

PREVENTION

If you are caring for a home aquarium with pet fish, chances are that you will have to deal with an ich infection at some point in time. However, there are certain measures that you can take which will greatly reduce the chance that your fish will become infected with ich. When purchasing fish from a pet store, try to examine them for any signs of ich parasites. Always put new fish in a quarantine tank for a period of time after purchase, in case they are carrying any parasites. If any of your fish begin to show signs of ich, it is very important that you remove them from the tank and place them in immediate quarantine.

CAUSES

Fish dropsy is usually caused by a bacterial infection, though the direct cause of this bacterial infection can be slightly more difficult to identify. Most bacterial infections in fish are the result of contaminated food or by the growth of bacteria in unclean aquarium conditions. It’s also possible that a fish may develop the symptoms of dropsy after experiencing kidney failure, liver failure or heart failure.

SYMPTOMS

The most noticeable symptom of dropsy in fish is a visibly bloated abdomen. This is caused by excess fluid building up in a fish’s body, which causes the resulting area to become swollen. Most fish afflicted with dropsy develop a ‘pinecone-like’ appearance, as the swelling of their body causes their scales to begin to protrude from their bodies. Loss of appetite, lethargy, sunken eyes and discoloration are all symptoms that may also be associated with dropsy in fish.

TREATMENT

The treatment methods for dropsy in fish usually involve the administration of antibiotics, though this may not be entirely effective. The best way to administer an antibiotic medication to a fish with dropsy is to add the medication directly to a fish’s daily food portion. As long as your fish is still eating, they will consume the medicated food before the antibiotic ingredient dissipates into the water. If you are feeding your fish a live or frozen diet, try to maintain a 1% ratio of the antibiotic ingredient to the amount of food. For live food, it may be necessary to prepare a diluted solution of the antibiotic and water, and then insert this solution directly into live food organisms by using a syringe. Try to only feed afflicted fish the medicated food, as they should already have been kept in a quarantine tank.

PROGNOSIS

In general, many fish afflicted with dropsy end up dying from this condition. The reason for this is that by the time their abdomen has become visibly swollen, internal damage from the excess fluid buildup is usually beyond repair. This is the main reason why it is important to diagnose and treat this condition in your pet fish as soon as possible. If you are able to catch a dropsy infection at an early stage, you will greatly increase the chances that your fish will respond well to treatment.

DROPSY
Dropsy (known as ‘Edema’ in humans) is a condition that results from a bacterial infection through unsanitary living conditions. Though dropsy is most commonly caused by a bacterial infection, it may also be caused by other environmental variants. Though dropsy in fish is not extremely contagious, it’s still very important to quarantine any infected fish as soon as you identify this condition. The most common symptom of dropsy in fish is a noticeable swelling of a fish’s abdomen.

TUBERCULOSIS
Tuberculosis in fish is caused by a bacterial organism that thrives in poor water quality conditions. Tuberculosis is commonly seen in fish from pet stores, or fish that live in extremely crowded conditions. The best treatment for tuberculosis in fish is a thorough tank cleaning, though prevention of transmission may sometimes require that you destroy the infected fish before the infection spreads to the rest of your aquarium. However, this is usually only necessary if other treatment methods are ineffective.

RED PEST
Red Pest is a bacterial infection that usually manifests as red, bloody streaks that appear on a fish. These reddish streaks sometimes progress to becoming open ulcerations. Since this is an internal bacterial infection, most topical treatment methods will not be effective for this condition. The best course of treatment is to add a small amount of antibiotic to your fish’s daily feeding ration. To help improve your fish’s chances of surviving this condition, it’s also recommended that you clean and disinfect your tank.

FUNGAL

SAPROLEGNIA
Saprolegnia is a type of freshwater fungus that can sometimes affect aquarium fish in freshwater tanks. When saprolegnia infects a fish, it causes a type of fungal infection known as mycoses. This type of fungus thrives in cooler water, and may sometimes be treated by raising the temperature of the tank by a few degrees. Infection with saprolegnia is often fatal to fish, due to the high reproductive rate, extensive cellular necrosis and severe epidermal damage caused by this fungus. Treatment for this type of fungus usually involves the additive of phenoxethol to distilled water at a 1% ratio. Phenoxethol may be available for purchase at some pet care supply stores, usually located in the fish care section. This solution is then added to the aquarium, or the area where the infected fish is being kept.

ICHTHYOSPORIDIUM
Ichthyosporidium is a fungus that is slightly unique, since it attacks a fish’s internal organs. This fungal infection usually spreads from the kidneys and liver into most of a fish’s other internal systems. The most common symptoms associated with this condition include external cysts, open sores, hollow belly and sluggishness. However, when a fish begins to display one or several of these symptoms, the fungal infection has usually progressed to an advanced point in which it can no longer be treated. The best course of treatment is to add certain medications to a fish’s daily food ration, such as chloromycetin or phenoxethol. However, these are fairly dangerous treatments, and may not ensure the survival of your fish.

INTERNAL OR EXTERNAL PARASITES

Because of the plethora of parasite species that can affect aquarium fish, it’s best to first group them into two specific categories:  ectoparasites and endoparasites. Endoparasites are organisms that infect a fish by infiltrating their internal organs and tissues. Ectoparasites are parasitic organisms that thrive by dwelling on the outside of a fish, such as on their gills, skin and fins. For the most part, the majority of parasitic organisms that affect fish are ectoparasites, with the occurrence of endoparasites being slightly rare in aquarium fish. In order for a fish to become infected with an endoparasite, it usually requires that they first ingest an organism that is serving as the intermediary host for the parasite, such as an insect or snail. Because of this, it is especially important to watch for parasitic infections when supplementing your fish’s diet with live food ingredients.

DANGERS OF PARASITES

The most commonly cited problem associated with parasitic infections is their incredible reproductive potential. By the time you are able to identify a parasitic infection in one fish, it is possible that the parasites have already reproduced to a point where they are currently in the process of infecting your entire tank. In an aquarium environment, fish are in close contact with all other inhabitants of the tank, causing parasitic infections to spread relatively quickly. Since parasites in aquarium tanks are easily able to transfer from host to host, they have extremely high survival rates in an aquarium environment.

SECONDARY INFECTIONS

In many cases, a parasitic infection in pet fish is also associated with development of some secondary infections. These secondary infections are mostly bacterial, and are usually the end result of feeding activities of parasites on a fish. Since many parasites either infiltrate the exterior portion of a fish’s skin through hooks, teeth or caustic skin-dissolving substances, this often results in open sores developing around the area affected by the parasitic infection. The irritation from these bacterial infections can sometimes cause a fish to produce excess mucus, sometimes resulting in respiratory problems. If a bacterial infection develops in addition to a parasitic infection, it may be necessary to treat with antibiotics. Since treatment for parasitic infections sometimes also uses certain antibiotics, it is very important to consult a veterinarian or fish care specialist about the best combination of medications that will work the best for treating your tank.

EXOPHTHALMIA

Exophthalmia can generally be referred to as a noticeable ‘bulging’ of a fish’s eyes. This is classified more as a medical syndrome than a disease, though there are some treatment options available. Symptoms of advanced exophthalmia  include partial or complete dislocation of the eye from its orbit and compression of the optic nerve with eventual blindness.

CORNEAL ULCERS

Corneal ulcers develop on a fish’s corneal area. The cornea is a protective layer that covers the eye area of most fish. When there are any disruptions on a fish’s cornea, an ulcer may begin to develop. This condition can become progressively worse, and may even eventually cause the eye to rupture. The most common treatment for corneal ulcers involves antibiotics that are applied directly to a fish’s eyes. However, corneal ulcers in fish are often treated with supplemental medications that are added directly to aquarium water in proper portions.

CATARACTS

Cataracts in fish are relatively rare, though may still be present in some cases of eye conditions. Technically, a cataract is a clouding of the crystalline lens of a fish’s eye. This reduces vision, and may inhibit a fish’s ability to properly feed. Cataracts are most commonly caused by a nutrient deficiency, though may also result from severe injury or trauma. Preventing cataracts in fish usually involves common sense procedures, such as ensuring that your pet fish is being fed a balanced diet.

CORNEAL EDEMA

Corneal edema is a condition that usually occurs when a fish’s cornea becomes inflamed or irritated. This results in excessive fluid buildup, which contributes to an opaque appearance of a fish’s eye. This is sometimes caused by a bacterial infection, and may be able to be treated with proper administration of certain antibiotic medications.

MISSING GLOBE

In some cases, a fish’s eye may deteriorate or become damaged beyond repair. This can be caused by any number of factors, though is most commonly seen in fish that are afflicted with tuberculosis, or fish that have recently sustained trauma to their head area. Eventually, the open socket of a fish’s eye completely fills with scar tissue after the damage has been repaired. Fish are able to function on a semi-normal level with only one operating eye, as long as you take measures to ensure that they receive proper nutrition. When feeding your fish, be sure that a fish with a missing globe is not being prevented from eating by other fish. If necessary, isolate this fish for designated feeding times, or give them their own quarantined tank.

CAUSES/RISK FACTORS

In most cases, fin rot is caused by bacterial growth that results from bad water quality. However, fin rot can also be caused by a fungal infection that rots the tissue of the fin in a more even manner. Needless to say, the quality of the water in an aquarium has a huge impact on how susceptible a fish will be to developing fin rot. In some cases, fin rot can also be caused by an injury to a fish’s fin, which then encourages a fungal or bacterial infection to develop. This is commonly seen in tanks that include aggressive fish species, since they may frequently nip at the tail or fins of other fish in the tank, resulting in injury. In addition to this, fin rot may also be sometimes caused by tuberculosis.

SYMPTOMS

Symptoms of fin rot are generally easily visible to the naked eye, and are usually characterized by a ‘ragged’ appearance of a fish’s fin tissue. However, this ragged appearance is more common in cases of fin rot that are caused by bacterial infections. In the case of a fungal infection, the tissue of the fin usually rots in an even pattern, eventually reducing the fin to a small stump. Bloody appearance of the fins, exposed fin rays, reddish spots on the fins and visible skin ulcers are some of the other symptoms that may appear when a fish is being affected by fin rot.

TREATMENT

Treatment of fin rot is usually a combination of topical antibiotics and specialized water treatments. If you are adding antibiotics to your aquarium’s water, try to dilute the solution in approximately 20 – 30 mg per liter of water. If you prefer, you can also add some antibiotics to your fish’s daily food portion. Some of the most common antibiotics used to treat fin rot in pet fish are tetracycline and chloromycetin.

PREVENTION

The best prevention method against fin rot is keeping your aquarium clean. Be aware of any changes in the quality of water in your aquarium, since this could be your first sign that your fish are more susceptible to developing health conditions. In addition to this, feeding your fish a balanced, highly nutritious diet is also a proven method that can help prevent fin rot. Use common sense when preventing health conditions in your fish – a clean tank is one of the best preventive procedures for ensuring that your fish do not develop fin rot.

STRESS

Betta fish are particularly susceptible to being negatively affected by environmental stress. Stress is a common problem among many different kinds of pet fish, and can manifest as some noticeable symptoms. Common symptoms of stress in betta fish include lethargy, clamped fins, spotted skin discoloration, open red or white sores, and difficulty breathing. Betta fish under extreme stress may also lay at the bottom of their tank, seeming to be motionless for long periods of time.

Stress in betta fish is usually caused by a problem in their environment, which may be identified through careful observation. Some betta fish may become stressed if they are currently living in poor water quality, or if they are suffering from ammonia poisoning. Betta fish may also become stressed if they have recently experienced a change in tanks, environment change (such as addition of new decorative tank elements), introduction of other fish to their tank, change in diet or undergone a stressful experience (such as a transfer to a temporary container for tank cleaning). Stress in betta fish may also become apparent if they are suffering from a health condition, such as fin or tail rot.

The best treatment for stress-related issues in betta fish is to first identify what is causing the stress, and then treat the specific problem. For example, if your betta fish is stressed due to an improper pH level in the tank’s water, adjusting the pH to the proper level will help to treat any symptoms of stress that the betta fish is experiencing.

FIN AND TAIL ROT

Betta fish are highly valued for their appearance, due to their brilliant colors and flowing fins. However, since the fins of a betta fish are larger than those of most fish, betta fish are also more prone to developing bacterial infections on their fins or tail. This is also known as “fin rot”, and is especially common in betta fish that live in poor water quality environments. Fin or tail rot may also occur in beta fish that are living in an overcrowded environment, or are subjected to the aggressive behavior of other fish in their tank.

OVERCROWDING

Betta fish are naturally aggressive fish, and it may take some care to ensure that they are not subjected to overcrowding. In general, betta fish do not thrive when kept with other fish, especially if all of the fish in question are male. Betta fish can be kept with certain species of fish, such as platies, corydoras catfish and loaches.

AMMONIA POISONING

Thousands of fish are killed each year from over-exposure to ammonia. Ammonia poisoning is most commonly seen in fairly new tanks. Ammonia poisoning can sometimes also occur after several new fish are added to an already established tank. The most common symptoms of ammonia poisoning are reddish gills, lethargy, difficulty breathing, or fish lying motionless at the bottom of the tank. After prolonged exposure to high levels of ammonia, a fish’s tissues will begin to visually deteriorate, causing eventual death.

MYXOBOLUS CEREBRALIS

Myxobolus cerebralis is a parasite that currently only affects fish in the salmonoid family. Species in the salmonoid family include trout, salmon, freshwater whitefish, chars and graylings. This parasite is commonly seen in most of Europe (including Russia), South Africa and the United States. Infection with this parasite causes a condition known as “whirling disease”, which causes neurological damage. The mortality rate for fish with whirling disease is approximately 90%. As of right now, this parasite has not proven to be transmissible to humans.

FISH ICH

Ich (also known as Ichthyophthirius Multifiliis) is a parasite that commonly infects many different types of fish. The disease resulting from an infection with the Ich parasite is called ichthyophthriasis, also called ‘white spot’ fish disease. Though fish ich is not always fatal, it can cause seirous complications if not treated in its early stages. In addition to this, if a fish is under significant stress (such as from change of environment or food type) this can sometimes result in much higher rates of mortality.

VHS
VHS (Viral Hemorrhagic Septicemia) is a viral infection that is often deadly in many species of pet fish. The condition of VHS is caused by the viral hemorrhagic septicemia virus, also called VHSV. This type of virus has several different types of strains, which may occur in many different areas of the northern hemisphere. This virus has not proven to be transmissible to humans through contact with infected fish. VHS was first discovered in the 1950s, when it was identified as affecting several different cultured salmonids. VHS was first documented as being in the United States in 1988, when it was discovered in infected almon returning from the Pacific ocean. Transmission of VHS to healthy fish is obtained through water transfer, contact with infected eggs, and from ingesting fish in contaminated areas. Symptoms of VHS typically involve mild to severe hemorrhaging of muscle, skin and internal organs. Other symptoms include reddish eye tint, bloated abdomen and noticeably bulging eyes. This virus is extremely hard to treat, though may be prevented by using an EPA-approved disinfectant.

OVIPARIOUS FISH

Approximately 97% of all pet fish are oviparious. The term oviparious refers to animals that lay eggs, without any of the embryonic development taking place inside the female animal of that species. In addition to being the most common reproductive method for most fish, it is also how many reptiles, birds, amphibians, insects, monotremes and arachnids reproduce. In most fish, this means that the eggs are laid before being fully fertilized, which is a process that takes place by direct interaction with a male fish of the same species. The term oviparious is directly opposite from the term ‘placental viviparity’, a reproductive process in which the embryo of a species reaches full development inside a female of the same species, eventually resulting in live birth of the animal’s offspring.

REPRODUCTIVE ORGANS

The two main organs in fish that are involved in the reproductive process are testes and ovaries. There is also a possibility that a fish will have several secondary reproductive organs, which are functional for increasing a fish’s overall fitness level. There are three different types of fish ovaries. Gymnovian ovaries involve the release of oocytes into the coelomic cavity, which then travel through the ostium and then enter the oviduct. In secondary gymnovian ovaries, the ova are shed into the coelom, which then results in them going direcly into the oviduct. In cystovarian fish ovaries, the oocytes are directly deposited into the exterior by traveling through the oviduct. Depending on a female fish’s species, they may have one of these three types of ovaries.

FISH REPRODUCTIVE METHOD

The general reproductive method for most fish involves the release of the unfertilized eggs from the female’s body, which usually then settle on the bottom of the fishtank. After this occurs, the male fish is able to pass by and fertilize the eggs when they are outside of the female’s body. The eggs reach maturity after they are fertilized, which can take a variable amount of time, depending on their species.

In some species of fish, the reproductive method is slightly different. Certain species of fish are classified as being “ovoviviparious” which means that the fertilized eggs develop inside the mother fish’s body. However, the eggs do not receive any additional nutrition from the mother, only surviving off the nutrition provided in the egg’s yolk. The mother’s body provides the eggs with respiration (gas exchange) in most cases.