the bottom of the tank. Incubation is short
and the remarkably large fry will appear
three or four days after the eggs are laid.
The adults are very proficient fry predators,
however, so steps will have to be taken to
save the fry. They are too small to be netted,
so either collect and move the eggs to a
hatching tank, or alternatively, move the
adults to a different tank after a few days
worth of eggs have been laid. Once the
adults are out of the tank, the fry will be
able to survive.
The fry are much larger than one would
expect—they can eat microworms or
vinegar eels immediately, and will also pick
at infusoria in the tank. After a week they
can be given baby brine shrimp, at which
point they will start to grow quickly. Once
they are half-grown (about ¼ inch) they
can be safely housed with the adults. The
development rate is rather impressive: the
fry reach adult size within two months, and
they start producing eggs and fry of their
own within three months.
Adult male Danionella translucida are smaller than females of the species.
Getting Your Hands
on the Micro Glassfish
The availability of D. translucida is
sporadic at best. They are rarely exported
for the aquarium trade, and when
they are, the losses can be huge. A few
specialty importers have been getting them
occasionally, so interested aquarists should
obtain them when they can, because there
is no predicting when they will show
up again. They are not difficult to breed
however, so tank-raised fish should be
more common in the future.
An important consideration
the susceptibility of this species to
environmental toxins. They have a low
tolerance for poor water quality and harsh
medications. The combination of being
extremely small and scaleless means that
normal concentrations of medications
can be toxic. If medicating is necessary,
avoid any chemicals not recommended
for scaleless fish and use half dosages
of everything else. Increase dosage of
medication slowly if the problem does not
get better, so that there is less risk of toxic
shock to the fish. Luckily this species is
otherwise very hardy and has not proven
to be disease prone.
D. translucida is a species that needs
to become established in the hobby. It is
interesting, easy to maintain, and is not
difficult to reproduce. They are certainly
conversation starters. D
An adult female D. translucida with mature eggs visible in her abdomen.
Adult female D. translucida are smaller in girth than the diameter of the yarn strands that make up
the tank’s spawning mop.
Tropical Fish Hobbyist www.tfhmagazine.com