The archer fish is a brackish aquarium species meaning that it lives in water having salinity level ranging between a freshwater and those saltwater. To explain further, brackish condition actually refers to the environment which is normally found in swampy areas close to beaches whereby you can find freshwater from streams ended up flowing to seas and over there you have water concentration which is a mix between the fresh and saltwater. Although there are quite a number of invertebrates (such as crabs and clams) and other fish species living in this special setup, none of them could be as interesting as the archer fish. So far, my experience with them are mostly confined to research which I did few years back thoroughly examining and studying their behavior and that has provided me a lot information about how they actually survive in the wild.
Setting up an aquarium to keep them as pets in home tank can be quite challenging. First being a brackish species, they require water with the right salinity meaning that you need to mix in some seawater salt into your freshwater as well. You can buy those from pet stores and if you are not sure what concentration you are getting and how much to dose in, I would suggest you get a hydrometer as well in order to get an accurate measurement. Although there won’t be any immediate effect that can lead to your fish falling sick, however prolonged failure to properly treat and prepare the water with the exact concentration (usually SG in the range of 1.003 to 1.006) can cause them to feel uneasy, the fish become jittery and easily frightened with your presence around.
Archer fish can be very efficient when it comes to hunting for their foods. Being a very patient and highly adaptive species which has evolved and develop their skills to survive in the wild harsh condition, their natural ability to shoot and spits out water means that they can devour land insects which are normally out of reach for most underwater fish species. Based on my observations, they will hardly miss their target (although sometimes they do) and what amazes me is that they can easily position themselves at the right angle avoiding light distortion and then accurately dislodge the insects causing them to slip and fall into the water.
When kept in man made home aquariums, you will need to prepare the environment very much similar like in the wild. Avoid filling the whole tank until brim full with water but instead leave at least half of it empty so that you can place branches and leaves and then cover the top part with aquarium hood to prevent the insects from escaping. Usually I use bogwood that rise above the water level or you can use tree trunks or either way construct a permanent elevated platform so that you can plant small shrubs with soil in a container.
Feeding them during mealtime is usually the most interesting aspect of keeping the fish because you can actually observe what they are doing until they managed to get their food. The water in which they are live in should be around 24 deg Celsius and care requirements for this species is very much similar just like any aquarium pet fish.
Article contributed by Simon Schmidt
Some other interesting fish species: Snakeheads