Why guppies die so fast is a really, really interesting question. The reason this is an interesting question is because it talks about a very specific experience. This question refers to those beautiful guppies you bought at the pet store, got them home, and then in a few days they were all dead. Meanwhile, your other fish are all fine!
Disclaimer: It Really Could Be Anything
It’s important to drive this point home: your guppies might be dying for so many reasons. In fact, they could be dying because of a combination of reasons. Things like water quality (ammonia, nitrites, nitrates), dissolved oxygen, wrong temperature, etc. Also, it could be a disease of some sort, ich, fish TB, fungus, a bacterial infection, a parasite, etc.
But, do you feel like you’re a fairly competent fishkeeper? Maybe, generally speaking, your other fish do alright. But, for some reason, every guppy you get just quickly fades and dies. Well, this is the article for you.
Main Culprit: Farm Bred Guppies Are Raised In Brackish Water
Let’s get right into it: ornamental fish farms often raise guppies in brackish water! This might surprise you, but lots of livebearers can live (and even thrive more so) in brackish water. In fact, mollies do well in full on saltwater!
So, this means that guppies born and raised in brackish water will not be accustomed to the freshwater most hobbyists (and pet stores) are going to keep them in. Consequently, your beautiful, new, vibrant guppies will suddenly and quickly fade. Eventually, they will die.
Why Do Farms Raise Guppies In Brackish Water Anyway?!
Fish farms raised guppies in brackish water for a couple of reasons.
Firstly is because guppies actually do a little better in brackish water than they do in freshwater. So, for the ornamental fish farms, it makes perfect sense to raise them in brackish water. They tend to suffer less disease in brackish water, and generally speaking, they are more robust.
Secondly, lots of guppy farms in Asia are located in areas of natural brackish water supplies. As such, the farms utilize that natural supply of brackish water rather than paying their water suppliers for fresh water.
Careful, Your Guppies Might Jump!
When we keep guppies raised in brackish water in freshwater they tend to be very uncomfortable and stressed. In turn, this stress and discomfort can encourage the guppies to jump from your aquarium in a desperate attempt to get out of the water that makes them so uncomfortable.
I Love Guppies Though, So What Can I Do?
So, having read this far, you might be feeling a little hopeless? Well, don’t despair. There are options for you to successfully keep guppies in your home aquarium.
Try Keeping Them In Brackish Water
The obvious choice is to keep guppies in brackish water, right? Well, yes, that does make sense. However, the exact salinity they were kept in will be unknown to you. Therefore, you might struggle to recreate the water chemistry in which they were born and raised.
Furthermore, if your plan was to keep guppies in your tropical community aquarium then it is likely that many of your guppy’s intended tank mates will not tolerant excessive amounts of salt in the water.
Better Yet: Find A Local Guppy Breeder!
So, if keeping them in brackish water isn’t the perfect solution, what is?
Find a local breeder! Local breeders are a great source of any aquarium fish, not just guppies. Local breeders almost certainly have the same tap water as you. That means the same hardness, and the same pH. As such, any fish you acquire from a local breeder will have no adjustment period or risks to health when settling into your aquarium.
And, considering the issue with farm-raised guppies and brackish water, a locally bred guppy (born and raised in freshwater, dechlorinated tap water) will be great for you.
Where Can I Find Local Breeders?
The easiest way to find local breeders is to either, a) join your local aquarium society, b) join a local aquarium Facebook group, or c) both!