By Simon Onabowale, BFAS
The
Gold Mixteco is one of three types of Mixteco (others are “Blue” and “Green”)
that originate from the Rio Coatzacoalcos system in Mexico. The word Mixteco
refers to a Mexican-Indian people from Oaxaca. This is a beautiful little fish
that grows slowly to about 6 inches and is relatively peaceful. At maturity
it has long flowing dorsal, anal and ventral fins and is considered to be a
good show fish. Although all three types are similar, the Gold form has more “yellowish-gold” coloring
in the gills. I obtained my starting group of 5 juveniles (about 1” in
length) from Rusty Wessel at a fish club auction and was told that he imported
them into the US in April 2003 so it is a relatively new fish to the hobby.
Indeed, it is difficult to find a lot of information about them on the Internet.
I started them off in a 15-gallon bare tank to get them acclimated to Bermuda
water. Water temp was 78F and pH 6.8. They were shy at first and darted around
a lot whenever someone approached the tank, trying to hide behind the corner
filter. After a few days it became apparent that the tank would be a bit small
so I moved them to a 30-gallon, displacing the pair of Jack Dempseys who lived
there before. The cycled tank had a thin layer of gravel with driftwood and several
plastic plants for hiding places. They liked this setup much better and began
staking out their own little territories.
Food
After the initial settling-in period, the Mixtecos readily accepted crushed
flakes, mini granules and the occasional bloodworm. They prefer to eat from
midwater as the food sinks but the more aggressive ones will pick from the
surface and dive back under cover. They will also scavenge through the gravel
and this causes problems with any live plants. They will pick at the roots
although they tend to ignore the leaves.
Sexing
Sexing the young is not easily done but as they mature the males of the sp. ‘Mixteco’ tend
to be slightly larger and, in my opinion, a bit more colorful. The most telling
differentiation is that females will have a bluish-black chevron on their dorsal
fin. As I soon found out, sexual maturity occurs at about 1.5”-1.75”.
I’m not exactly sure in terms of time, but I would estimate sexual maturity
occurred around 10-12 months of age. As luck would have it I ended up with
4 males and (fortunately) 1 female.
Breeding
The hardest part about the breeding process was getting a pair bond. Males
and females did not seem to naturally pair up and it would be a good idea
to start with a larger group. The ‘Mixteco’, like other Thorichtys
species, is a substrate spawner. Eggs were laid on a cleared out area and
both parents took turns guarding the eggs. It became apparent when a pair
bond has formed as a number of things happened:
the male and female remained together in a set area of the tank (where the eggs were laid)
they developed pronounced vertical black bars on their sides and other colors (gold and blue) became more vivid
they actively chased all other tank mates away
Once the bond was formed, the couple staked out a region of the tank, made a pit in the gravel and deposited the eggs. They then both watched over the eggs until they hatched, even to the point of ignoring food. Eggs are very small and if you’re not looking for them they’re difficult to see. The fry hatched in 36-48 hrs although this could differ depending on temperature. I had a heater in the tank, keeping the temperature at about 80 degrees.
 |
 |
|---|---|
Breeding pair – female on left ... note the bluish mark on the dorsal
fin. Male, showing the darker vertical bands, is guarding the fry. |
Outsiders banishes to the top corner of the tank. |
Caring for Fry
The fry were very small at first – about 1/8 of an inch and, naturally,
defenseless. Because of their small size it is advisable to use a cover on
your filter intake so they don’t get sucked up. I find a small sponge
is good as it helps to add a microscopic food source for the fry to pick at.
It looked like the spawn size was about 30-40. They tended to huddle around
in a little ball while mama and papa fended off any intruders. It was interesting
to watch the parents as they would actually “round up” any wanderers
by sucking them into their mouths and spitting them back into the group. The
fry, at that point, stayed near the bottom of the tank and picked at any morsels
on the bottom so it is important to have a cycled tank that will provide a
certain amount of natural bacteria/algae/infusoria. As they grew, the fry were
able to take small portions of finely crushed flake food. The parents also
helped by breaking up larger flakes and spitting out the crumbs which the little
guys ate up. I added small amounts of frozen brine shrimp twice a week.
As mentioned previously, the parents, particularly the male, became more aggressive
whilst guarding the fry and showed his colors along with dark vertical bands.
He chased away any intruders so you need either a large tank to give them space
to get away, or remove any other fish. To maximize the longevity of the spawn
I chose to remove the other ‘Mixtecos’ back to the original 15-gallon
tank. The parents appeared to be responsible guys so I left them with the fry.
I knew this was a risk as they may have turned on the fry but I was out of
tanks so I went the “natural selection” route.
Everything was okay for a couple of days until I realized that the pair bond
had broken and the male was now chasing the female away. She was looking a
little tattered and torn. Apparently this is not uncommon in the Thorichthys
species. Live and learn…I removed the female to the 15-gallon tank with
a divider and all returned to normal. Papa was quite happy raising the kids
and showing his colors (through the glass) to the other fish.
Twice weekly water changes with the same temperature water seemed to keep everyone
content. So far, so good, as after 3 months I don’t seem to have suffered
any mortalities. The fry are about ?” long now and are starting to develop
their coloring.
Conclusion
To summarize, breeding the ‘Gold Mixteco’ is not difficult under
the right conditions. Getting a pair bond was the hardest part so it may be
best to start with a group of six or so and let the pairing occur naturally.
Keeping water temperature in high 70s and feeding the occasional bloodworms
seems to help the spawning process. Once spawning has occurred it is important
to watch the dynamics of the tank as the male parent may become aggressive
to other tank-mates (including the female eventually). Good filtration and
twice weekly water changes should be all you need to keep this fish happy and
alive.