Although typically encountered in bait shops rather than pet stores, mummichogs are quite interesting fish that deserve more attention from aquarists. The basic information provided here is also applicable to a wide variety of closely related species that are found throughout the world.

Mummichogs are native to the coastline of the United States, from Maine to Texas. They belong to a group that is broadly termed the “killiefish.” This order, Cyprionoformes, contains over 500 species, including such aquarium favorites as guppies, mollies, and swordtails.

Mummichogs are commonly found at the mouths of rivers, in tidal streams, purely marine environments, and, occasionally, in waters that are nearly fresh in character. Female mummichogs reach a length of 5 inches, with the males being a bit smaller and more brightly colored.

Mummichogs take well to a wide variety of environmental conditions and seem equally at home in seawater or water that is only slightly brackish. Individuals that are slowly adjusted to freshwater aquariums will survive there quite well also. They are fairly tolerant of low levels of dissolved oxygen and are active at both cold and warm temperatures.

In nature and the aquarium, mummichogs form large schools, the behavior of which is quite interesting to observe. As is true with many such fish, captive mummichogs seem more comfortable in large groups. Males in breeding coloration are extremely attractive fish and, despite frequent courtship displays, rarely fight with each other.

The mummichog's appetite knows no bounds. They do best on a varied diet of animal and plant based prepared foods. They also relish algae disks and vegetables and will become particularly ravenous when presented with live or frozen foods. Mummichogs are highly effective feeders and will easily overwhelm more passive species with which they are housed.