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Dropsy isn’t actually a disease, in fact, it is a symptom of kidney failure in your guppy. When your guppy’s kidneys fail, its body cavity and tissues fill up with fluids causing its body to swell, eventually to the point where the scales stick out to the point your guppy looks like a pinecone.
So you have looked into your guppy tank and noticed one of your guppies is swollen! Assuming you know it isn’t a pregnant female and you don’t think it is constipation, it could be Dropsy.
I have been keeping guppies for 30 years or more, and over that time I have had a number of fish suffering from Dropsy. It isn’t nice to see and my heart sinks whenever I come across it. All is not lost when we discover a guppy with Dropsy.
So now we know Dropsy isn’t a disease, but rather a symptom of a problem, let us have a look at some of the potential causes and then what we can do to prevent and cure.
What Causes Dropsy In Guppies?
OK, without getting bogged down in a science lesson, let me quickly explain how a guppy’s kidneys work. Unlike humans, who have to drink water to consume it, guppies can absorb water through their skin in a process called osmosis.
Water enters the body through the skin or the gills, but water also has to leave the body, just like in humans. It is the kidney’s job to ensure wastewater leaves the guppy’s body. If the kidneys fail, the guppy’s body will swell with all the excess water.
What Can Cause Kidney Failure In Guppies?
The number one cause of kidney failure in guppies is stress. Stress is essentially a guppy killer!
Stress can be brought on by internal parasites or illness, overcrowding, bullying, poor diet, or, most likely, by poor water quality. Poor water quality is very stressful on guppies. It is really important that we as fishkeepers carry out regular water changes on our aquariums to keep our water in good condition.
I try to change 30% of the water in my guppy aquariums every week, just to keep the levels of waste down.
How To Treat Dropsy In A Guppy?
At the first sign of Dropsy in your guppy or guppies, move all the affected fish into a quarantine tank. This will give you the ability to observe the fish with the problem and assess what the potential cause may be.
Once you have placed the guppies into quarantine, I would carry out a large (50% or more) water change on your guppy aquarium. That way, if the root cause is poor water quality, you have addressed the issue immediately.
The guppies that are placed in quarantine can now be observed. If they have signs of disease or illness, treat that problem as a matter of urgency. The disease may be stressing the guppies causing their kidneys to fail.
If there are no outward signs of illness or disease, try adding a small amount of salt to the quarantine aquarium. Adding 1 tablespoon of aquarium salt for every 3 gallons of water in the tank might be enough to help draw the excess water out of the guppy. I use salt to treat a lot of guppy ailments. Guppies normally tolerate salt very well.
If you are in Europe, eSHa 2000 is recognized as a fantastic treatment for Dropsy.
If after a few days the dropsy doesn’t show any signs of going away, then, unfortunately, there isn’t a great deal you can do, other than giving your guppy time. If they are eating and swimming well, then the longer you can give them the better. If however they are clearly in distress and struggling to swim, the only course of action may be to humanely euthanize your guppies.
Dropsy can be a real problem to guppies and we as fishkeepers should do everything we can to stop it from affecting our guppies.
First and foremost, keeping our aquarium water clean and as free from waste as possible is the best course of action to prevent Dropsy in the first place.
If you are unfortunate enough to have a guppy with Dropsy, first place the fish into quarantine, then try to work out the root cause of the Dropsy to stop other fish from having the same issue.
Treating Dropsy is very difficult, so prevention is the best way to go.