What causes Dropsy in guppies?

To be fair, it's nothing that you may be doing, but rather than poor genetics when it comes to guppies and other super popular freshwater aquarium fish. Dropsy is normally just a term for when a fish has liquid collecting inside of its abdomen when it shouldn't (and hence its bloated, scales that are spike-like).

Li0nFish, I'm sorry to hear about the loss of your guppy. Dropsy is a common problem in fancy guppies, and as Avery mentioned, it is usually caused by poor genetics. Unfortunately, there is not much you can do to prevent it.

Overfeeding can contribute to dropsy, so it's a good idea to monitor how much you're feeding your fish. You could try feeding them smaller portions more frequently throughout the day instead of one big meal. Also, make sure you're not overstocking your tank as this can lead to poor water quality, which can also contribute to dropsy.

Keep an eye on your remaining fish and watch for any signs of illness. If you notice any bloating or other symptoms, it's best to quarantine the affected fish and treat them with medication.

I hope this helps and that your other fish remain healthy.

I am so sorry to hear that you have lost guppies to Dropsy. It is something that can not really be helped or prevented and it can happen to anyone.

Most of what has been explained above will help a lot in trying to prevent it to som extent but it is probably not something you have done at all.