Pandora's Aquarium

Most of the time, troubleshooting by frequent water changes and avoiding fish stress (see tips in Basics if you are a beginner) will prevent serious outbreaks of disease in the tank. Off the list of preventative things, I cannot stress buying small numbers of fish SLOWLY enough; many a tank can be devastated by bringing in a large number of new fish in a relatively small time. Healthy fish can actually cohabitate with some disease organisms at low concentration without becoming symptomatic, but when fish are stressed by sudden environmental changes and overcrowded conditions, their immune systems don't function well and they become far more susceptable to disease^{2, 6, 16}. New fish especially are vulnerable, because they have been passed from breeder to wholesaler to distributer to retailer to consumer and most likely spent the whole time in horrid surroundings. They should be quarantined in a separate tank whenever possible.

Some diseases can be tenacious once they take hold in a tank. Be sure to try and figure out a general diagnosis before dumping a lot of medication into the tank, as some meds are toxic dyes that can kill with overdosing (especially to sensitive fish such as tetras and scaleless cats), and some, such as antibiotics, will wreak havoc on your biofiltration and throw your established tank into a new cycle. Keep in mind that "sometimes the cure can be worse than the disease" (and ALL chemical additions to the tank which change water conditions stress the life inside the closed environment). Also, keep in mind that most plants and inverts will not tolerate many medications in the water. In planted aquaria, it is best to remove the affected fish to the quarantine tank or into a small treatment vessel with circulation and heat. It is sometimes helpful to add a small (1tbsp/5gal) amount of aquarium salt (NOT marine salt, which is different), as most medications disturb healthy gill function, and the salt reduces osmotic shock and electrolyte loss... but this is a somewhat controversial issue that I address in the following article (pros & cons): To Salt or Not to Salt?.

I've been working on a photo archive of fish diseases that people send me or allow me to use from their sites. This list and archive of photos is not meant to be exhaustive or comprehensive. Please note also that some diseases have multiple manifestations (Columnaris, NTD, Fish TB, to name a few), and may vary in presentation from fish to fish; others are not true "diseases" caused by a single organism, but rather signs that could point to a number of causative organisms (dropsy, pop-eye). Click on the thumbnails, and you will be linked to the larger photos (if it was larger to begin with, that is, I can't enlarge photos any larger than they were when sent to me, because this will not improve resolution).

THIS IS AN ONGOING PROJECT THAT IS ALWAYS BEING ADDED TO. IF YOU HAVE A RELATIVELY CLEAR PHOTO OF A FISH WITH A DISEASE THAT YOU THINK I CAN USE, PLEASE EMAIL ME. WITH SPECIFIC DISEASE PROBLEMS SEEKING A CURE, I PREFER THAT YOU USE THE MESSAGE BOARD LINKS IN THE CONTACTS SECTION RATHER THAN EMAIL.

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Ich (or Ick)	Ichthyophthirius multifiliis (FW) Cryptocaryon irritans (Marine counterpart)	Distinct, sometimes slightly-raised white spots that look very similiar to grains of salt or white sand on the skin.	Scratching against objects (skin irritation), clamped fins, may "hang" and gasp near surface if infection reaches the gills.	Numerous treatments: brand names include Mardel's Maracide or Coppersafe, Jungle's Ick Guard, Aquarium Pharmaceuticals' Super Ich Cure, treatments that contain formalin, etc. Take special note of warning labels; copper is not safe for invertebrate animals or plants, malachite green (ingredient in large majority) is dangerous for scaleless fish and many small tetras (halve dosage). Marine formulations slightly different. Most medications not tolerated well by corals and inverts. Best treatment for marine fish is QT, feeding garlic and use of cleaner fish/shrimp.	Perhaps the most common disease of pet fish. Tends to attack stressed fish, especially with rapid temperature and pH fluctuations. Easily treatable with caution if caught in time, but may be recurrent if not treated for at least a week. Cysts live in gravel, has multiple life cycle stages, read my article for more treatment options. Water changes, raising temperature (to speed life cycle), darkening of tank, etc. all recommended. Guard for secondary infection of wounds by bacteria.Certain fish, such as gymnotoids (FW), hatchetfish (FW), batfish (SW) and tangs (SW) especially susceptible.
Courtesy of TFH Magazine	Courtesy of Anonymous (left the photo big, so you can see very nice close-up of individual ich spots)	Courtesy of Bob Johnson	Courtesy of "Matt"	Courtesy of "Bryce"	Courtesy of Dave Pettit (please note: not typical of this disease, since larger spots likely represent coalescence of individual grains, also seen on dorsal fin; in addition, possible coinfection with lymphocystis)

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Bacterial External Infections Columnaris (specific to F. columnaris); Often Misnamed "Mouth Fungus" Fish Tuberculosis/TB Skin Infection (specific to Mycobacterium spp.)	Various organisms. Positive diagnosis not possible outside of lab culture & microscopy (not practical for most hobbyists). Gram positive: exceedingly rare in FW fish; small handful of SW species, but most primarily do not attack skin. Gram negative: Flexibacter columnaris, Aeromonas spp., Pseudomonas spp., Vibrio spp., Salmonella spp., many others not listed. Non-stainable: Mycobacterium spp., mostly M. piscium & M. marinum	White, clear, red/pink areas of necrosis. Occasionally slightly ragged/fuzzy appearence. Inflammed patches and sometimes deeper ulcers develop. Various patterns of appearence and presentation. Columnaris usually presents near the head and sides of the body and is often mistaken for a fungus; it is characteristically white and patchy.	Various: lethargy, hiding behavior, "hanging", clamped fins, loss of appetite, general constitutional signs.	Broad spectrum antibiotics. (Examples include but are not limited to: Maracyn I & II, Jungle Binox, Aquatronics Kanacyn, etc.). Frequent water changes a must to improve quality. Tuberculosis is difficult to treat because it attacks intracellularly.	Frequent water changes a must to improve quality. Test for ammonia, nitrites, nitrates. Columnaris perhaps one of the most common skin infections of pet fish (livebearer fish and certain other fish especially susceptible). Specifically for F. columnaris, read this article by Dr. Barb. Fish tuberculosis (though not transmitted by the same species that causes human tuberculosis) can be transmitted as zoonosis called "fish tank granuloma" on hands with open wounds (again, another article by Dr. Barb discusses this issue. Use gloves if reaching in the tank with suspect animals.
Courtesy of Chuck's Hobbies & Pets (shows columnaris infection)	Courtesy of Shawn Prescott (shows tuberculosis infection)	Courtesy of Anonymous (shows aeromonas infection)	Courtesy of Qian Hu Inc. (uncultured specimen, pathogen unidentified)	Courtesy of Karen Wall (uncultured specimen, pathogen unidentified)	Courtesy of Michele Hartley (uncultured specimen, pathogen unidentified)
Courtesy of Vincenzo "Noodles" Nood (shows tuberculosis infection, with classic appearance)	Courtesy of Natalie (sharp picture, uncultured specimen, pathogen unidentified)	Courtesy of Charlie Calhoun (uncultured specimen, pathogen unidentified)	Courtesy of Charlie Calhoun (uncultured specimen, pathogen unidentified)	Courtesy of Vincenzo "Noodles" Nood (shows columnaris infection)	Courtesy of Alan Perry (shows a skin infection which has caused trismus in the mouth)
Courtesy of Laura (shows an infection which has affected the first ray of the dorsal fin, though appears not to have begun fin rot yet)	Courtesy of Adam	Courtesy of Adam	Courtesy of Elena Wong	Add your photo here	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Swim Bladder Disease	Various; Often indigestion in goldfish and other "balloon" breed fish, but may be bacterial infection in other species. Occasionally, sudden trauma such as when fish are jostled excessively in transit or "dumped" into water without acclimatization may result in fatal injury to the swim bladder.	May show some limited bloat, but usually no real physical changes.	Fish has great swimming upright despite active attempts to do so. May occasionally float "belly up".	Different depending on species; goldfish are very susceptible and sometimes cured by discontinuation of diet and salt bath, followed by change in diet to high fiber digestible foods. However, other fish may require antibiotics and have a worse prognosis. Recently introduced fish that exhibited signs within a matter of minutes have the worst prognosis of all, and there is often no cure for trauma to the swim bladder.	Most common in "pot-belly" shaped breeds of fish, such as goldfish & parrot cichlids due to blockage and insufficient fiber/vegetable matter in the diet. However, many fish that suffer trauma or excess stress, or just get an internal bacterial infection that occurs on or around the swim bladder may have problems. Baby fish fry that have swim bladder problems are commonly known as "belly sliders" (most scoot around the bottom fo the tank, unable to swim up, or spin uncontrollably in the water). It is still unknown if this is the same exact disease entity or what the cause is, but most attribute it to congenital or developmental causes, sometimes birth defects, premature birth or inadequate nutrition at certain stages. They should be culled to prevent suffering.
Courtesy of Qian Hu Inc.	Courtesy of Nick Beach (shows "twirling" behavior, a futile attempt to swim)	Courtesy of Kevin Carroll	Add your photo here	Add your photo here	Add your photo here

VIRAL INFECTIONS/TUMORS

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Lymphocystis Cauliflower Disease	Lymphocystis spp. (A DNA Iridovirus)	Viral infection that causes cells to become megaloblastic, thus forming small tumors (bumps or growths), often along the lateral line or the pedicle, where the fin meets the body. The tumors sometimes take on the appearence of tiny cauliflowers, thus the name.	Lethargy, general symptoms, may affect balance and swimming control if along the lateral line.	There is no consistently proven treatment that always cures lymphocystis. Many companies that manufacture antiparasitic cures make claims, but these will not cure lymphocystis, which is non-protozoan and totally different. There is a new treatment called Acriflavin which may be promising, but only with mixed results so far.	Frequent water changes and reduction of ammonia and nitrites in water may reduce stress to help the fish battle the infection and shrink tumors on its own. Interestingly, cyprinids & catfish which have been studied appear to be resistant.
Courtesy of Lars Lonstromm of the Laboratory of Aquatic Pathobiology	Courtesy of John Black	Courtesy of Tom Choi	Courtesy of 2la from The Age of Aquariums (not characteristic of usual presentation of disease)	My own photo (Taken at a local pet store which will remain unnamed.)	My own photo (Another view of the same fish)
Courtesy of Vincenzo "Noodless" Nood	Add your photo here	Add your photo here	Add your photo here	Add your photo here	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Solid tumors of unknown cause	Not fully understood in fish or man. Many oncoviruses may be suspect in turning off genes involved in tumor suppression. In fish, just as in other animals, may be benign or malignant (cancerous).	Growing mass of tissue, can occur on almost any part of the body.	Usually not overtly affected unless the tumor is very fast growing internally, or obscures vision, feeding, or swimming.	None for most fish. Seek veterinary help for large and/or expensive fish. Surgery often the only cure, though rarely will shrink back on its own.	Not much known about the fish oncology at this time. Watch tumor closely for fast, uneven growth of tumor. If it keeps the fish from feeding and/or swimming, consider euthanasia.
Courtesy of The Welborn Pet Hospital.	Courtesy of Joel Rose	Courtesy of Joel Rose	Courtesy of Ron Travelbee from Badman's Tropical Fish	Courtesy of Ron Travelbee from Badman's Tropical Fish	Courtesy of Mike Hottovy
Courtesy of Alice Dodge	Courtesy of Anonymous	Add your photo here	Add your photo here	Add your photo here	Add your photo here

EXTERNAL ARTHROPOD PARASITES

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Anchor Worm	Lernea spp.	Actually, lernea is a copepod (crustacean arthropod) rather than a true worm. It looks like a small whip (a few mm to under an inch long) attached to the fish at the mouth end and with a forked tail.	Usually none noted unless very severe with secondary infections.	May be physically removed, but will cause great stress to the animal, and must be done carefully and with a dab of antibiotic over the wound afterwards. Brand name formulations like Jungle Parasite Guard and Aquarium Pharmaceuticals may also help.	Rarely seen in pet fish not kept outdoors (in ponds), and usually then only in ones that have been fed live foods.
Courtesy of The Dept. of Western Australian Fisheries	Courtesy of Qian Hu Inc.	Courtesy of "JJ"	Courtesy of "JJ"	Courtesy of John Childers (this photo is one of the best high-resolution photos I've ever seen of its kind; really captures the anatomy of this parasite in detail)	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Fish Louse	Argulus spp.	A flat disk-shaped arthropod parasite with many legs. On the fish itself it is barely noticeable only as a flat, dull colored bump that you may just think is a part of the fish, unless you see the legs themselves or the disk moving around on the body.	Usually none noted unless very severe with secondary infections.	May be physically removed, but will cause great stress to the animal, and must be done carefully and with a dab of antibiotic over the wound afterwards. Brand name formulations like Jungle Parasite Guard and Aquarium Pharmaceuticals may also help.	Rarely seen in pet fish not kept outdoors (in ponds), and usually then only in ones that have been fed live foods. Crustacean not related to true lice, which are insects.
Courtesy of Niklas Gustavsson (beautifully clear image of fish louse out of water!)	Courtesy of Niklas Gustavsson	Courtesy of Qian Hu Inc.	Courtesy of Pet Care Forum (shown stained)	Courtesy of The Aquatic Animal Health Research Institute	Add your photo here

TRUE WORM PARASITES (TREMATODES, NEMATODES, CESTODES)

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Flukes (Skin, Gill, or Eye)	Dactylogyrus vastator (Gill Fluke), Gyrodactylus sp. (Mostly Skin Flukes), etc.	Gill flukes may show with red, inflamed gills, but otherwise many fish flukes are microscopic (some of the largest being just a few mm, but mostly smaller), and so confirmed diagnosis by physical appearence alone is not possible. Confirm with a vet or lab.	Scratching, gasping at surface (again a nonspecific sign that has other more common causes, see comments at right).	A good, thorough discussion of treatment options can be found in dan's archived comments on fluke treatment.	No photos are included here, because usually flukes are too small to visualize with the naked eye. This also creates serious problems for trying to diagnose by general physical signs (hyperproduction of slime, inflamed gills) or general behavioral signs (listlessness, gasping, scratching, etc.). All these signs overlap considerably with other more common causes of skin and gill irritation, including ammonia poisoning and more common skin parasitisms such as ich. The first step in any tank where these signs are seen is to rule out ammonia poisoning first by testing for any level above 0.
Courtesy of Cindy Buors (blurry photo of worm-like parasite on gill; large for most gill flukes, which are difficult to see with the naked eye; may possibly be another type of external parasite)	Add your photo here	Add your photo here	Add your photo here	Add your photo here	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Roundworms	Unknown nematode species (metacercarean form)	As shown below as an infection of connective tissue (usually internal worm infections cannot be seen externally and often affect the gut; in these cases, they have migrated to muscle tissue).	Loss of appetite, lethargy, etc.	Try Clout or an antiparastic medication for large parasites (formalin and many methods were tried on the first cases below without success). There is also some good information on the treatment of camallanus worms as contributed by Jason Parry.	Please read my article, Worms in my tank?? before jumping to the conclusion that any worm in the tank is a parasitic or disease causing worm. The large majority of small worms seen in the aquarium not attached to the fish are free-living and harmless (the ones shown below are an obvious exception). Most of these true parasites shown below require a fish host at some time in their life cycle. They often come in with contaminated live foods such as Tubifex worms.
Courtesy of Mike Spafford (unknown/possible sparganosis of nematode infection attacking muscular tissue)	Courtesy of Mike Spafford (unknown/possible sparganosis of nematode infection attacking muscular tissue)	Courtesy of Mike Spafford (unknown/possible sparganosis of nematode infection attacking muscular tissue)	Courtesy of Mike Spafford (once again, Mike comes through, this time with one of his clearest photos to date; note very small thread-like nematode on skin, circled)	Courtesy of Tom Lorenz	Courtesy of Tom Lorenz
Courtesy of Anonymous (an interesting photo sent to me; moving nematode was found between the scales of a large koi)	Courtesy of Natalie (camallanus worm extracted from a gourami; these nasty parasites can often be seen dangling from the anus of infected fish and can removed physically with care & difficulty; see fish louse removal above)	Courtesy of Kevin Piper (another unpleasant photo of camallanus worms protruding from a fish)	Add your photo here	Add your photo here	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
N/A	Unknown--those shown below could have a number of causes--they could be bacterial infections that formed pus-filled cysts under the skin, they could be true tumors (see above), Lymphocystis, cysts that formed around worms, etc. Because I was uncertain, I didn't want to mislabel them, so I keep them here in the hopes that they will still help someone, if they see something similar. For a more thorough discussion of various causative organisms, please refer to dan's archived comments on "unknown lumps & bumps".	Varies greatly.	Varies greatly. May have no affect on behavior at all, depending on cause. If near the mouth and it hinders eating, could have obviously faster consequences.	Unknown, may be incurable in some (if they turn out to be true tumors); depends on individual case. For those exuding pus and fluid and/or those cases where behavioral lethargy and malaise is seen, try an antibiotic. More detailed information on different treatment options that can be attempted can be found in dan's archived comments on "unknown lumps & bumps".	These pictures shown below may span a wide range of different causes. Some are clearer than others.
Courtesy of Mike Spafford (case shown above is recurrent; suspect lympho, but without certainty)	Courtesy of Yew Wee Tan (this didn't look like any classic "textbook presentation" of anything that I knew of, except possibly a clumping bacterial or fungal nidus on the trailing caudal fins; photo clarity didn't permit me to say for sure... if anyone has any idea of this being more specifically characteristic of something else, please let me know)	Courtesy of Michele Hartley (beautiful photo of a true hollow cyst; I believe that it may have originated with a bacterial infection just under the skin, and then grown enormously due to pus accumulation; fish shown above died within a relatively short time of first appearence)	Courtesy of Mike Spafford (only a small dimple lesion is shown; would otherwise have classified problem as being due to injury with secondary bacterial skin infection, but unsure etiology due to history of worm infection in same tank, see above)	Courtesy of Luigino Bracci (amazingly clear photos of such a small, darting fish; it is beyond my knowledge what this growth could be, it was described to me as an adherant circumscribed and object that the owner believed may have been a parasite; however, it is larger than and distinct from most of the common fish parasites I am aware of)	Courtesy of Luigino Bracci (amazingly clear photos of such a small, darting fish; it is beyond my knowledge what this growth could be, it was described to me as an adherant circumscribed and object that the owner believed may have been a parasite; however, it is larger than and distinct from most of the common fish parasites I am aware of)
Courtesy of Nick Austin (beautiful series of 3 professional-quality photos; appear to identify the same multiloculated, fluid-filled cyst)	Courtesy of Nick Austin (beautiful series of 3 professional-quality photos; appear to identify the same multiloculated, fluid-filled cyst)	Courtesy of Nick Austin (beautiful series of 3 professional-quality photos; appear to identify the same multiloculated, fluid-filled cyst)	Courtesy of Mike Silverman (the owner of this fish did not know what these lesions on the snout were either; whether or not they are lympho, some other viral growth or lesion is hard to determine from the photo, but they do appear on an otherwise healthy fish)	Courtesy of A. Ort (appears to be a large, single & perfectly circumscribed, fluid-filled cyst)	Courtesy of "Jeders" (a series of growths/cysts causing extensive deformity of the head of this guppy)
Courtesy of Zac (having seen more and more of these kinds of lesions, I'm really curious what it could be, and would appreciate input if it looks characteristic of something. This lesion looks much like the fungus-like lesion on the neon tetra shown above)	Add your photo here	Add your photo here	Add your photo here	Add your photo here	Add your photo here

Graphic/Pictoral Links (these sites MUST Have photos to be linked directly below)

A very special thanks to Dr. Andrew Reiner, Wei Khee of Qian Hu Inc., Tony of World Cichlids, Alyssa of Jungle Labs and "Dr. Barb" of Flippers & Fins for taking special interest in helping with this site's creation. My great appreciation goes out to all who donated photos and made this site possible.

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Pop-Eye	Various organisms (nonspecific), Severe Stress	Exopthalmos (protrusion of the eyeball from the socket) caused by accumulation of pus and fluid in the infected orbit.	Associated with loss of vision, also just general signs of lethargy.	Broad spectrum antibiotics. Many formulations available. For a more thorough discussion on the various causes & treatments of popeye, please refer to dan's archived comments about popeye.	Frequent water changes a must to improve quality. Test for ammonia, nitrites, nitrates. Pop-eye is a sign of a number of infections, rather than a disease in its own right. For more on this disease, read this
Courtesy of Pet Care Forum	Courtesy of Joe Azzopardi (Jazzo) of The Age of Aquariums	Courtesy of Anonomous (also illustrates dropsy)	Courtesy of Qian Hu Inc.	Courtesy of TJ Schwertfeger (unusual case with hemorrhagic pooling in the eye; unknown etiology)	Courtesy of TJ Schwertfeger (unusual case with hemorrhagic pooling in the eye; unknown etiology)

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Cloudy Eye	Various organisms (nonspecific), Severe Stress, Malnutrition, Cataracts, Old Age, Hyperproduction of slime due to poisoning, bad water quality, or irritation	A cloudy white or grey "haze" over the eyes that may cause blindness.	Associated with loss of vision, also just general signs of lethargy.	Investigate if water quality is high first (water changes), then if nutritional needs of that species are being met. Wait at least a week or two before trying any antibiotics, it will often clear on its own if water quality is high.	Frequent water changes a must to improve quality. Test for ammonia, nitrites, nitrates. Cloudy eye is a sign of a number of things, rather than a disease in its own right.
Courtesy of PistolPete73 from Reef Central (also illustrates somewhat serious case of popeye, see above)	Courtesy of PistolPete73 from Reef Central (right eye only; also illustrates somewhat serious case of popeye, see above)	Courtesy of Planet Catfish	Courtesy of Qian Hu Inc.	Courtesy of "Sharkie"	Courtesy of Vincenzo "Noodless" Nood

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Fish Tuberculosis/TB Systemic Infection	Mycobacterium spp., mostly M. piscium & M. marinum	Various presentations, hard to make certain diagnosis without necrospy or lab culture. Includes: wasting away, shrunken stomachs, occasionally skin infections, spinal curvature deformity in advanced cases.	Various: anorexia/refusal to eat, lethargy, hiding behavior, "hanging", clamped fins, loss of appetite, general constitutional signs.	Difficult to treat because it attacks intracellularly and multiplies within macrophages (the fish's own defense system). Try a strong antibiotic such as kanamycin sulfate or streptomycin. Euthanasia must be considered in bad cases.	Fish tuberculosis (though not transmitted by the same species that causes human tuberculosis) can be transmitted as zoonosis called "fish tank granuloma" on hands with open wounds (see photos, below). Use gloves if reaching in the tank with suspect animals. M. marinum can be a serious skin infection in people! If a rash such as this developes, especially if you have a marine aquarium, make sure your hobby is known to your doctor. Read this article for more info.
Courtesy of Connie from Acmepet	Courtesy of Mr. Chris from The Age of Aquariums	My own photo (wasting looks more pronounced in real life)	Courtesy of MonkeyDog from Reef Central (shows a photo of Fishtank Granuloma on the arms of a reefkeeper caused by the marine bacterium Mycobacterium marinum. Was a bad case with several complications.)	Courtesy of MonkeyDog from Reef Central (shows a photo of Fishtank Granuloma on the arms of a reefkeeper caused by the marine bacterium Mycobacterium marinum. Was a bad case with several complications.)	Add your photo here

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Dropsy	Various organisms (nonspecific), poor water quality	Bloated appearence with scales that stick out like a pine cone. Best viewed from above. Dropsy is not really a specific pathologic entity, it is to describe a general condition of fluid accumulation in the internal body cavity, which has many causes. Dropsy usually signals internal infection and multiple organ failure. It can be compared to ascites in humans in end stage kidney failure.	Lethargy, lack of appetite, grave constitutional signs.	Unfortunately, dropsy is usually incurable and fatal; however, in rare cases, spontaneous recovery may occur. A strong antibiotic such as kanamycin sulfate can be tried, but because it is an internal infection, usually it does little good.	Take measures to improve water quality immediately. Fortunately, it is not highly contagious.
Courtesy of Qian Hu Inc.	Courtesy of Judith de Vos (mantis) from The Age of Aquariums	Courtesy of JoAnne Burke of PureGold	Courtesy of Anonomous (also illustrates pop-eye)	Courtesy of Anonymous	Courtesy of Cindy Downs (illustrates mild case that recovered with salt bath)

Common Name	Pathogen/Cause	Physical Signs	Behavioral Signs	Potential Treatment	Other Notes
Hemorrhagic Septicemia	Various organisms, Ammonia spike	Distinct bright red streaks on fins (caused by vascular inflammation due to systemic/bloodborne bacterial infection) and occasionally patchy red discoloration on the flanks of the body.	Depends on severity of condition. If due to ammonia, may show in conjunction with hyperventilation (fast breathing) and gasping at the surface, erratic swimming, etc.	Broad spectrum antibiotic. Can resolve spontaneously in some fish if source of water quality problem is removed.	Check water quality, especially if fish exhibiting other signs of ammonia poisoning (gasping at surface). Regular water changes and measuring of ammonia/nitrite (especially if relatively new tank) are a must. In FW, commonly seen in goldfish due to their naturally high ammonia output. In SW, often seen in tangs due to their inability to tolerate sudden water quality changes and susceptibility to shock.
Courtesy of Qian Hu Inc.	Courtesy of Steve Horswill-Johnston	Courtesy of Mark Delgrosso	Courtesy of Sylvia Bernard	Courtesy of Caroline Ellis	Courtesy of "Squiggly" (danio pictured here)

Courtesy of Michele Hartley (illustrates fight injury in male bettas that jumped barrier)	Courtesy of Michele Hartley (illustrates fight injury in male bettas that jumped barrier)	Courtesy of Kamphol (shows a normal gravid loach [the equivilent of "pregnant" for egglayers]--obviously not a disease state, used here only for the purposes of comparison with pathologic causes of bloating)	Courtesy of Julie Waite (though this was labeled as NTD by the contributor, and though it may well be a case of it, I left this in the "other" category due to the fact that a number of other infections can also cause large delineated losses of color, though not usually in as abrupt a fashion as this parasite)	Courtesy of Nathan Cantrell (superficial skin injury secondary to trauma; likely at this point not yet seriously infected, but may be in a subacute time frame)	Add your photo here
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