Siamese Fighting Fish (Betta Splendens)

..and why you should think twice before buying one!

Betta fish are commonly found in pet stores all over the world, most often being kept in tiny cups or jars. The reason that this is possible for the betta fish and not other species, is that the betta fish not only has gills, but has a labyrinth organ, which allows it to breathe air from above the surface of the water just like you and me. Unfortunately, humans have exploited this trait in order to force them to live in tiny spaces since they do not require proper underwater flow or aeration to survive. They have become nothing more than another piece of home decor, even placed in tiny terrariums with nothing but plant roots to eat.

In the wild, betta fish live in shallow waters with low oxygen such as marshes and ponds, which is why they developed a labyrinth organ to survive. However, they do not live in tiny spaces and are always surrounded by plants, rocks and natural debris. Furthermore, they are only found in tropical waters of 24°-28° and will not survive for long in anything colder. They are carnivores whose diet consists mainly of insects and cannot survive by nibbling on plant roots. Just like any other animal, they require adequate space and an environment as similar to their natural habitat as possible in order to thrive.

The most important reason to never keep a betta fish in a cup of water is that no fish should ever be kept in small amounts of water. Fish produce waste just like any other animal, which pollutes the water around them. Without enough water to dilute this waste and a filter/plants to help mimic an ecosystem for removal, this quickly builds up and becomes toxic to the fish. No one deserves to live in their own filth!

How to maintain your own ecosystem

What you really need to keep a happy and healthy betta fish:

A tank of at least 10L with plants or decorations for your fish to swim around and hide in, allowing it to feel safe.
A heater that can be set to 24°-28° to mimic tropical water temperatures
A filter which helps keep the water cleaner for longer and aerates the water so your fish can breathe underwater as well as above it. You will need a low-flow filter if you pick a betta with long fins, as they are not strong swimmers.
Proper food for your fish, ideally a mix of pellets and frozen insects from a pet store
To be content with only having one fish! Male bettas are territorial and will fight each other to death... hence the name "fighting fish". Females can be kept together (called a sorority) if you have a big enough tank.