In turn, these fish are preyed upon
by swift-moving predatory species, by
aquatic turtles and snakes, and especially
by wading birds that spear individuals out
of a school with their long, pointed beaks.
While all these predators can severely
shorten life expectancy in the wild, captive
longevity can surpass five to seven years,
depending on the species.
Of the commonly available species of
danios, the zebra danio is the most widely
known. Hailing from India, Bangladesh,
and Pakistan, the zebra danio is one of
the smaller species. Large adults seldom
exceed 2 inches in length. Body coloration
in the wild-type zebra danio is silvery
white, striped in black to deep metallic
bluish longitudinal bars. One of the very
first tropical fish to ever be kept in U.S.
and European aquariums, the zebra danio
is truly a pioneer species of the industry. Its
hardiness and versatility have allowed it to
be selectively bred, such that a wide variety
of unique cultivars whose coloration,
pattern, and finnage vary significantly
from the wild-type have come into being.
Some cultivars include the long-finned
variety, whose dorsal, pectoral, and caudal
fins are delicate and elongate.
One of my favorite zebra danio cultivars
is the leopard-spot variety. This morph,
whose black lines have been broken into
speckles, wears spots of dark on a silvery-tan base that is reminiscent of the mottled
coat of a leopard. A particularly stunning
animal is the long-finned leopard variety,
which bears the hallmarks of both the
spotted leopard pattern and the long,
elegant finnage of the long-finned cultivar.
Although aesthetically beautiful to say
the least, this cultivar is not nearly as
hardy or as long-lived as the wild-type
zebra danio. Prone to nervousness and
poor health (namely bacterial infections
when housed in unsuitably cool or filthy
water conditions), these animals cannot
be expected to fare as long in captivity as
their wild-type brethren.
And of course, there is the always-controversial GloFish™. A transgenic
animal bearing a cnidarian gene for red
coloration, this fish wears a radiant coat
of electric pink to neon red that is unlike
anything seen in natural tropical fish.
While the original was red, other colors
are now available as well. A school of
GloFish™ can add an unprecedented
Courtesy of Segrest Farms
exceed 6½ inches in length and attain a
bulk that is easily several times that of a
zebra danio, the giant danio is an active
schooler that can add both color and
activity to the community tank.
Requiring much larger environs than
their zebra kin, the giant danios prefer
long, deep aquaria that are outfitted with
plenty of tall grasses and leafy plants
(either artificial or living will suffice).
Because of their large size and endlessly
active movements, these fish can easily
intimidate other, smaller species such as
neon tetras, rasboras, and hatchetfish.
Mix with hardy, schooling fish of similar
size. Tiger barbs, red tailed sharks, and
various catfishes mix well with giant
danios, as do other danio species, as well
as loaches, small freshwater eels, and
other bottom dwellers that will keep out
of the swimming range of the danios.
Some cichlid keepers use these danios as
splash of color to your tank. When
these fish initially appeared, there was
considerable speculation about possible
horrors that they could cause, but these
fears are without scientific foundation.
Nevertheless, they are illegal in some
Likely the most easily cultivated egg-laying fish species in the hobby today,
the zebra danio is an excellent choice for
beginner breeders who wish to learn more
about how to cultivate fish in the home
Transgenic GloFish™ zebra danios carry a cnidarian gene for red coloration.
Second only to the zebra danio in terms
of availability and popularity are the giant
danios in the genus Devario. Sandy to tan
dorsally and ventrally, this species wears
stunning silvery to golden splotches and
broken lines atop swatches of cobalt blue
along their flanks. Taking the common
name from the fact that these species may