Heterandria formosa female

When most people start keeping fish, the mention of livebearers brings to mind an image of a guppy with a long, flowing, colorful tail or a molly with a large sail-like fin. Most do not realize that there is a livebearer native to the southeastern United States that is one of the best beginner's fish available! It is undemanding, tough as nails, and can be kept in a small tank. With all these qualities, it is hard to believe that Heterandria formosa are not mainstream hobby fish.

These fish do not require any special care. Give them a tank with clean water and feed them on a regular basis and they will do well. Give them some plants to swim through, be they real or fake, and they will thrive! Even beginners who are prone to mistakes can have a thriving colony of Heterandria formosa in no time to do how hardy they are.

When we first start out keeping fish we are all prone to mistakes. Ours is definitely a hobby of trial and error learning. One of the reasons these fish are so good for beginners is that they will withstand most of these mistakes. They are tolerant to some ammonia for those who do not know about tank cycling at first. They are comfortable at room temperature in most houses and will withstand a lot more fluctuation than many fish. Even if someone accidentally cranks the heater and the tank is 90 degrees Fahrenheit, the fish will live for a while, giving the aquarist time to catch their mistake and turn it back to normal.

One of the big advantages that Hets present is that they need less space than most fish given their small size. Females reach 1.25 inches in total length while males reach only 0.75 inches! This ranks them as the smallest live bearing fish! It also means that they can be kept in much smaller tanks or you can put more of them in a larger tank. Assuming their water is kept clean, a 2.5 gallon critter carrier with some gravel and fake plants will suit a handful of fish just fine!

It is hard to talk about Heterandria formosa without mentioning their unique method of reproduction. Given their small size, the females cannot hold large broods of fish like some of their larger cousins. Instead their reproduction system is similar to an assembly line and they produce a fry or two every few days. This means that there are always baby fish in the tank! Obviously this should make them popular with younger kids who will feel like they are taking great care of their fish when they see the tiny new additions.

So why are these fish not more popular?

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