Author: Doris Sarslow
Month (classic years): Jan/Feb
original AquaNews publication: 1991 Jul/Aug
Uses Article Format: YES
credits: illustration by Doris Sarslow (1991)

When I was new to the hobby I thought the only livebearers were guppies, Platys, and mollies - that sort of thing - since this is all that I saw in the pet shops I frequented.  It wasn't until I became acquainted with an all out certified fish nut did I realize how wrong I was.  Still, it was a full year and a half before I became familiar with a livebearer that, if not the smallest known, it came pretty close.  I'm talking about Heterandria formosa.

These fish, who max out at about ¾" - 1” for females and 1/2” - 3/4" for males, are actually a native of the united states ranging from North Carolina to Florida and along the Gulf Coast into Louisiana.  They have been found to live in both fresh and brackish waters and seem to favor the more shallow waters thick with plants.  They can handle a wide variety of temperature from 500-900Fahrenheit and are ridiculously easy to breed.  As was quoted by a friend, "Just drop two of them in a tank and soon you'll have hundreds".  This is, perhaps, a slight exaggeration but not by much.

heterandria formosa doris19

The basic body color of these fish is an olive-gray with a dark line running along the lateral line.  This line is crossed at regular intervals with bars that run about 1/4 of the body depth above and be low the line.  Depending on the fish, sometimes these bars are difficult to see.  The dorsal fin has a dark spot at the base and all the fins have a yellowish tint.

As was mentioned earlier, this fish is very easy to breed. Simply take a two, five, or ten gallon tank, fill it with water, add some plants (java moss is good), a filter of some sort, and a boy and girl H. formosa.  Before long you'll have "hundreds".  The females will drop 2-3 fry a day for about 10 days and them will take a break for about two weeks before starting again.

The fry can be raised on infusoria (which can be found in algae or the java moss), daphnia, brine shrimp, microwonns, and whatever the parents are eating.  H. formosa are not known for eating their young so they can all be kept in the same tank.

Although these fish are seldom seen in pet shops, they are not difficult to find - at least in my area - so why not add this little livebearer to your fishroom and pick up a few more BAP points?