Introducing: Livebearers
by Ruby Bayan
The term "livebearers" means that these fish do not lay eggs.
Instead, they give birth to live, fully formed young which are
capable of swimming and feeding as soon as they are born. The
eggs are fertilized and develop inside the body of the female.
Since these young fish are born live and swimming, the broods
are usually small in number. Each group usually averages 20 to
50 fish.
The male members of this livebearing species have a
gonopodium, a sex organ formed by the fusion of several rays of
the anal fin. During mating, this gonopodium is directed
forward, toward the female. With the help of tiny hooks at its
tip, this specialized fin gets briefly attached to the cloaca of
the female while sperm is channeled into her.
The unique thing about livebearing females is that they are
capable of storing sperm. This gives them the capability to
develop several successive broods from just one mating session.
Guppy 
The guppy is a native of South America, Barbados, and
Trinidad. But because of its hardiness and ease of
proliferation, the guppy is now commercially bred and available
in many fish farms in America, Asia, and Europe.
At one time, the guppy, which prefers a diet of mosquito
larvae, was deployed" to different areas as a countermeasure to
fight malaria. Recently, exotic breeding has given rise to
rainbow-colored, large-finned varieties that are a delight to
own.
Guppies do well in aquariums filled with either fresh or
brackish-water. They prefer well-planted setups and love to
explore them. They will be happy in a community tank as long as
there are no aggressive fish that will nip at their fins and
tails. Populate your tank with males and females since the males
will tend to pick on each other's tails if there are no females
to catch their attention.
Molly 
Also native to the South America region, the sailfin and the
hybridized gold, black, albino, and lyretail mollies prefer
hard, alkaline water that can get as cold as 68 degrees
Fahrenheit. Known to thrive best in brackish to marine waters,
mollies have been used to help "mature" start-up marine
aquariums. They are relatively easy to care for, as long as the
waterconditions are kept to their liking. If the water quality
is deteriorating or too cold, they will clamp their fins, sit
still on the substrate, or move about listlessly.
Like all livebearers, molly males are distinguishable by
their gonopodium. The male sailfin molly has a well-developed
dorsal fin that he uses to catch the attention of the female.
Platy
and Swordtail
Platies and swordtails are just as fertile and prolific as
the guppies. They are also popular among tropical fish
aquarists. Cross-bred and hybridized extensively, platies and
swordtails are now available in various color combinations and
fin types. Originally greenish, with the male having a single
orange caudal fin extension (or sword), the swordtail has now
been cross-bred with the platy. This has led to the creation of
the Xiphphorus variatus that can be of marigold, sunset, tuxedo,
or tiger colors There are also elaborate double swords
(lyre-tails) and high-fins (topsails) in black, albino, red, and
tuxedo. Platies and
swordtails can really fill up your tanks quickly. There is
little difference between platies and swordtails. The male tail
of the swordfish is the most noteable difference and can grow up
to 1 inch
Feeding and
Breeding Livebearers
by Ruby Bayan
How to Feed Livebearers
Guppies, mollies, platies, and swordtails are all omnivorous.
They eat live, frozen, and freeze-dried food, as well as plants
and algae. They will be the first to snap at food still floating
on the water surface, though they will also chase after food
floating beneath the surface, and pick on those that have sunk
to the bottom.
Since guppies are quite small and have tiny stomachs, they
get full quickly; and then want to feed again in less than an
hour. Swordtails and mollies are also known to be almost
non-stop eaters; they seem to be hungry all day. You can feed
them small meals more frequently or, because they also have a
fondness for plants and algae, you can let them pick on the
greens in between flake and live food meals.
Be sure to provide a variety of foods, preferably live ones,
because a nutritious, complete diet will enhance their colors
and ensure good health. Keep in mind that they will eat their
young if given the chance.
Speaking of the young, the best food for livebearers’ fry
are: powdered food, freshly hatched brine shrimp, crushed
hard-boiled egg yolk, cultured microworms, and infusoria (green
water). Observe the fry carefully. As soon as they have
completely absorbed the nourishment from their attached yolk
sacs, introduce the food. After a few days, gradually convert to
adult food (like mashed flakes or tablets), making sure the
particles will fit in their mouths. |
Black
Molly (Poecilia sphenops):
This is a jet-black fish with quite unusual dorsal fins (in males).
With enough space the dorsal fin can become very big. This is
normally a very active fish. 
Sailfin Molly (Poecilia velifera):
Another impressive looking Molly, gets its name from its
dorsal fin. The body is normally dark green, but in this picture it
the albino/gold variety. Can get very big. 
Guppy
(Poecilia reticulata): This
is a very popular fish, probably because each Guppy's colour is
unique. Females tend to be larger and more duller.