Monos (Monodactylus argenteus)
Along with scats, monos are among the most popular of the brackish water fish. Their extended dorsal and anal fins render these beauties most “angel-fish like” in appearance. With their bright coloration and active lifestyles, monos are ideal subjects for larger aquariums.
Various species of mono are found throughout a huge range extending from the east coast of India to Australia and New Guinea. The background color is silver, with areas of yellow on the dorsal, anal, and tail fins. A black line goes through the gill plate, and the eyes are often a startling blue in coloration. In body form, they much resemble fresh and saltwater angelfish.
Monos are fish of river mouths, protected bays, and sheltered coastlines and can tolerate fluctuations in salinity.
Monos are extremely active fish and require a large aquarium. In the wild they form large schools and should be maintained in groups of at least four. In smaller groups, distinct hierarchies form, and less dominant individuals are harassed and prevented from feeding.
Monos are often maintained in marine aquariums at pet stores. Be sure to determine the specific gravity at which your fish has been held, and make adjustments slowly if your own aquarium water is brackish.
Captive monos are active feeders and may out-compete less aggressive species. They do best on a diet that contains a good deal of plant material, and particularly relish kale, dandelion, and other greens.