Dropsy, is actually
a "symptom" and not a disease in itself. The standing scales
and blown up appearance are the result of swelling within the tissues
and organs of the fish due to a build up of fluids in the kidneys and
an inability to excrete this fluid in a normal manner. In other words,
advanced kidney dysfunction.
The problem with treating this disease is that there are a number
of "potential" causes: bacterial infection, parasites,
cancerous tumors, virus', internal fungal infections or sudden temperature
drop of more than 3 degrees.
If the cause is bacterial, the swelling typically comes on pretty rapidly.
If swelling is gradual then one or more of the other potential causes
are more likely. Unfortunately, treatment is most often useless
at this point due to the advanced state of the disease process. When
the illness, whatever the cause, has progressed far enough to cause
internal swelling, the concomitant internal damage is usually too extensive
to be repairable.
The latest research has shown that if the disease cause is bacterial
and if the disease process is caught early enough, treatment with Romet
B, a broad spectrum antibacterial, *may* be effective when used concurrent
with an increase in water temperature to 84-86ºF for 2 weeks minimum.
BE CERTAIN to maintain HIGH OXYGEN LEVELS during such treatment since
at these temperatures, water holds significantly less oxygen at these
higher water temperatures. One of the suspected bacterial precursors
to the disease process -- Aeromonas, is killed at these temperatures.
Concurrently add 1/8 teaspoon of EPSOM SALT -- per 5 gallons of water.
Feeding foods soaked in ERYTHROMYCIN will kill the second suspected
bacteria, Mycobacterium. In rare cases popeye has been found to be caused
by Edwardsiella etarda. This is found *only* in fish that have been
bred in outdoor ponds -- the functional bacteria in this case is carried
by frogs. While fair to good results in treatment have been found by
feeding Romet B., even better results have been found using injectable
chloramphenicol or amakacin. This is best done by your veterinarian.
If parasites are a known cause, treat for them first for 3 days increasing
the temperature to 86ºF as fast as possible.
EPSOM SALT may help reduce the internal pressure caused by the swelling.
Extremely good aeration is necessary here due to the use of such high
NEVER USE SALT (sodium chloride, a.k.a. aquarium salt) for treatment
of dropsy. This will KILL your fish in a very short time. The affected
fish are already having a difficult time getting rid of salts due to
kidney dysfunction. This causes the blown up appearance and concurrent
scale standing. The osmotic imbalance caused by addition of sodium to
your tank water will make this condition far worse.
EPSOM SALT on the other hand, does not pass through the walls of
the gut or gills and will extract water OUT of the surrounding tissue
into the gut where it *may* be excreted.