Re: NANFA-L-- How do you breed Notropis?

Mysteryman (bestfish-in-alaweb.com)
Tue, 19 Jul 2005 23:10:32 -0700

David Sanchez wrote:

>I collected some Notropis hypselopterus. I am very
>intrested in breeding them. Can anyone offer any
>advice?
>
>Dave
>
>
First of all, the name is Pteronotropis, not Notropis, so knowing that
may help improve your results on a google search or whatever.

Otherwise, boy, did you come to the right place. I'm sure that no less
than two dozen of us have spawned Sailfins, and I'm equally sure that
they'd all agree that it's pretty easy. In other words, you couln't have
picked a better fish to start with in this group.

Some guys will quibble about what is necessary and what isn't, but here
are some things which will help:

1-- These fish spawn when the water warms up after the winter. Actually,
they'll spawn a few times a year, but late spring seems to be the
biggest season for them.
2-- To apply that in aquarium terms, cool the tank down to simulate
winter. Cool it down into the 60's and leave it there for a month or
two, with the photoperiod down to 8.5 hours a day. During this time,
feed the fish very well on good foods. They will spawn on ordinary fish
flakes, but adding some live or frozen stuff will certainly help.
3-- Simulate spring by letting the temp creep back up a degree every few
days and increase the photoperiod by 15 minutes every other day. this
will stimulate hormone production in the fish which will in turn ripen
eggs and sperm. The fins of the males will grow as well.

The tank itself: These guys will spawn in a 10-gallon tank, but not as
well as they will in a 20 or 30 long. This fish is fairly picky about
it's environment; as you probably noticed when collecting them, didn't
you see how they were only found in certain little places? You want to
try to simulate that kind of place in your tank. One surefire way I
found to do it is to use a long tank, and put the filter on one end of
it. On that same end, the tank is lit and planted. ( a full hood won't
work for that, so I use a 10-gallon light on a 30 gallon tank. You'll
notice that the fish will tend to stay on the darker half of the tank,
away from the strong water current but yet away from the dead spot on
the extreme opposite end. As for substrate, pea-gravel works well. The
gaps in that gravel are big enough for the eggs to fall down into, safe
from being eaten. While the fish prefer sandy bottoms in nature, that
lets them eat the eggs too easily, and they sure will!
The water should have a pH around 6.8 and a temperature of 74. Using a
piece of driftwood or some amazon extract to make the water a little
tannic will help a lot, and the water hardness should be low to lower
medium.
Water changes stimulate spawning.
I find that making water changes with distilled water a few times a week
( 15%) as the temperature approaches 73-74 sets them off spawing like
crazy. The same is true for many other Pteronotropis species. They spawn
for a few days and finally stop, but a water change will make them start
again, and you can usually get quite a number of spawns out of them for
a couple of weeks like that.

Spawning-- these fish are egg-scatterers. A male or group of males will
chase a ripe female around the tank, doing their little courtship
dances. When the fish get near the glass walls of the tank, they can
feel the change in water movement, with their weberian apparatus, caused
by the mantle of relatively still water coating the glass. This is what
they're looking for, and when they find a good spot, the male(s) will
poke the female with his snout, which has some little spawning
tubercules on it, to stimulate her to drop her eggs. Sometimes the male
will wrap himself around the female and spray his milt while she drops
the eggs in a big bunch, and sometimes she'll only drop a few and the
males will scramble to fertilize them before the chase resumes.
You've probably noticed how these fish tend to hang down in the lower
1/3 of the water column? Spawning fish really hug the bottom, so if you
should notice a few fish swimming on the bottom well below the others,
pay attention because they may be spawning or getting ready.

Theeggs hatch in about 3 days. The fry hide for the first day, and then
make a mad dash for the surface. You'll see them all along the surface,
up against the glass. They are surprisingly strong and agile swimmers
for their age and size, which is about half the girth of a baby guppy.
Since the fry stay-in-the top and the adults stay-in-the bottom, the fry
don't get eaten as much as you might expect. Still, it's a good idea to
scoop them up with a jar and move them to a rearing tank where they can
be fed well. A week of greenwater suits them well, and after that first
week they will eat flake food ground into flour with gusto. At that
point they're as easy to raise as guppies.

This method has proven pretty much foolproof for me, but there are
numerous people here who have spawned them easily without going to
anywhere near that much trouble. Considering that, you should probably
try the methods the others are sure to describe very soon and see how
that works for you before trying my method. Central Florida doesn't get
as cold in winter as South Alabama, so your local fish may be a lot
easier to please without any wintering period
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