The characins are a large group of freshwater fishes found in South and Central America and Africa. They are characterized by the Weberian Apparatus (the linkage of bones between the swimbladder and the inner ear) that allows them to hear high frequency sounds.
Despite their reputation for being difficult, it is possible to keep some killifishes in a community aquarium, and here three species spring readily to mind: Aplocheilus lineatus (Sparkling panchax) Pachypanchax playfairi (Playfair’s panchax), and Oryzias latipes (rice fish or medaka). These are surfacedwelling species, so they make a useful addition to the aquarium in that they occupy an area of the tank that is usually ignored when buying fishes.
The egglaying Cyprinodonts have always been regarded as difficult because they are believed to require special conditions, namely soft acid water, but while this is true for some species it certainly isn’t the rule for all of them. Many are exceptionally colourful and this alone makes them good aquarium fishes, but to see them at their best requires dedication on the part of the aquarist. It takes a lot of time and patience to maintain banks of small species aquaria, remove eggs from spawning mops, or dry out peat and then raise the fry. For those of us who have kept killifishes the work involved is worth it. If you haven’t very much space, then try with a single species tank.
