These are one of the
newer species of Melanotaenia rainbowfish to be seen in the
obtained a group of adults, approximately one year old, which consisted of four
females and a single male. The adult
males have a much higher body than the females and have a little bit more of an
intense color to them. Males can
start to be sexed out at about four months of age at the size of one and a half
inches by their color and body shape. I
must add the females do show some nice colors, more so than many other
Melanotaenia species, making them just as desirable as the males.
The group was housed in
a twenty-gallon high aquarium, which was filtered by a single Hydro-sponge
filter. The bottom had a couple of
handfuls of crushed coral scattered about to bring the pH up to about 8.0.
Temperature was maintained steady at seventy-eight degrees Fahrenheit.
A large acrylic yarn mop (I prefer to use dark green yarn) was placed on
the bottom and another floated in the aquarium.
Diet consisted of frozen bloodworms, live blackworms, live baby brine
shrimp and assorted flake foods, all which were eagerly accepted.
Once to three times a day they were fed.
Within days of setting
them up, the floating mop was pulled and found to contain several tiny, clear
eggs. As the fish settled in to
their home, more and more eggs were found more often.
Pretty much anytime the floating mop was checked, eggs could be found.
Notice I said "the floating mop"; I found it rather odd that I
rarely ever found an egg in the sunken mop, even if it was the only one in the
tank! To hatch the eggs, I remove
the mop and place it in a one or two gallon container which is filled with water
from the spawning aquarium. I add an
airstone with a gentle airflow and place the container in a darker part of the
fishroom away from any direct or bright light.
It takes about ten days for the eggs to hatch and I found that a good
many of them do hatch. The problem
now is feeding the tiny fry. At
hatching, the fry are just over one millimeter in total length and as thin as a
hair..if you don't know that you're looking for tiny fry, you'll miss
First foods I offered
were Euglena and "sponge scrunge" (the squeezed dirt and debris from a seasoned
sponge filter); in addition, I added a small piece of Java Moss, which houses an
assortment of smaller "bugs" the fry may feed on.
The numbers of fry seem to increase for a few days as more eggs hatch,
but soon the number of young decline as the days pass.
It takes about a week before microworms seem to be taken by the
youngsters and another week for newly hatched brine shrimp. What
started out as a container of maybe a hundred and fifty fry, after ten days,
will be down to a couple dozen. From
that point the fry are easy to grow out. The
last catch to them is the rate of growth - which is very, very slow!
At four months the fry will range from three quarters of an inch to one
and a half inches.
If you are a Rainbowfish
fancier and don't have these guys, I'd have to tell you that you should add
them to your fishroom "wish list". With
their attractive colors, peaceful behavior, easy maintenance and rarity, they
should fit that "need" for the oddball hobbyist.
Eric Bodrock, Aug. 2004