This is a suggestion for those who have always wanted to have an aquarium, but were unsure about what kind of fish to put into it. After all, some fishes can be a bit boring, behaviour-wise, so if you want your aquarium to be more than just a kind of screensaver or animated wallpaper, the archerfish is the way to go, for it has one of the most adorable hunting behaviours you’ll ever find. In its preferred natural habitat, the mangrove forests of South-East Asia, there’s a lot of vegetation floating on and hanging over the water, with many delicious bugs on them. Only, they’re just out of reach.
Luckily, this charming and large-mouthed little fish has developed the perfect weapon for this: a water gun. It can shoot jets of water with remarkable force and accuracy to shoot insects down from the branches they rest on. After positioning itself just below the surface of the water, it takes aim by adjusting for the refraction of light at the water surface with its eyes, and forms a kind of gun barrel between its tongue and the roof of its mouth. Then, like a bellow, it quickly presses its gill covers down, forcefully expelling the water from its mouth. It almost never misses, and is accurate to over 1,5 metres. It can also make fairly impressive jumps when a bug gets too close to the water surface.
And so the best bit is, the Archerfish can be kept in an aquarium. It takes more work to feed it than your average goldfish (plus you have to be willing to handle live bugs), but the show of frantic watergunning and leaping from the water you get in return is definitely worth it.