Hemigrammus ocellifer - Steindachner
1863
by David Snell
From Delta Tale, Vol. 32, #3. Potomac Valley Aquarium Society
Aquarticles
I purchased a pair of Head-and-Tail Light tetras from the Centreville Aquarium shop in
late October 2000. I put them into my tetra conditioning tanks. As with other Hemigrammus
species, it’s fairly easy to distinguish the males from the females. The males are
more slender than the females, while the females appear to be more full and round in the
midsection. Also, when viewing the females head-on, the females that are filling up with
eggs appear visibly wide.
The conditioning tanks had a pH of 6 to 6.3 and a conductivity of 380ms. The tetras
were fed mainly frozen bloodworms, live blackworms, newly hatched brine shrimp, and live
fruit flies. In a few weeks’ time, the female was very noticeably filling with eggs.
For my spawning tank, I had set up a 5.5 gallon tank that was filled with about 3
gallons of RO water, with a conductivity of 50ms, and a pH of 6.3. The water temp. was
about 78-80°F. The water was treated with a double dosage of Kent Blackwater Extract. I
attached a small piece of Java moss to a small lettuce clip that was attached with a
suction cup to the back glass panel. On the bottom of the tank was my home-made spawning
grate that would allow the eggs to fall to the bottom of the tank and be separated from
the adults above. Since tetra eggs can be light sensitive, the tank was covered with a
dark towel to reduce the amount of light.
The pair was placed into the spawning tank on November 19th. Two days later in the
morning, the pair had spawned. I noticed there were about 300-400 eggs. It looked like
about 10% of the eggs had already fungused. The adults were immediately returned to their
conditioning tanks. I was concerned that more eggs would fungus during the course of the
day so I left the towel covering the tank.
Within 24 hours, the eggs started to hatch and I could see wigglers on the bottom of
the tank. The fry only looked a few millimeters long and they looked like small slivers of
glass. With in 36 hours it appeared that all the viable eggs had hatched. There were 300
or so fry on the bottom of the tank. By the second day, I added ½ cup of water from my
paramecium culture to make food available to the fry when they became free swimming. As
with the Hemigrammus erythrozonus fry, I found the H. ocellifer
“hanging” on the glass nearly motionless.
On the third day, I added another ½ cup of paramecium to the spawning tank. By the 5th
day, all the fry were free swimming. The number of paramecium visible in the tank had
declined. On the 6th day, I decided to try and start feeding the fry newly hatched brine
shrimp. Although the fry appeared to be too small to consume newly hatched brine shrimp,
the fry were able to eat it with out much problem. At this point, I discontinued feeding
paramecium and continued the newly hatched brine shrimp.
I started doing water changes about once a week with more RO water. The Head-and-Tail
Light tetras seem to grow more slowly when compared to the growth of the Glowlight tetras.
The 5.5gallon tank was not likely the ideal size tank for raising them.
Over the course of the next two months it was clear that the number of fry were
declining, but the strong remained. At about 6-7 weeks, the color of the fry started to
look like the adults with the noticeable “head and tail” light. At about 2.5
months, I had about 80-100 remaining tetras. I moved about half the tetras to my 75 gallon
planted tank, and I auctioned off the other half in 4 bags at the PVAS 2001 Winter
auction.
|