Breeding Corydoras davidsandsi
by Allan James
First published in the newsletter of the Greenock & District
Aquarist Society (Scotland), and scotcat.com
Aquarticles
This species from the Aeneus Group is found in the middle
stretches of the Rio Negro in Brazil and is a look-alike. It has the same colouration as C.
metae from the river of the same name in Colombia, but davidsandsi has
a longer snout and the black stripe carries on into the bottom lobe of the caudal fin,
while C. metae stops short at the caudal peduncle. The C. melini connection
has melini having the same black body stripe ending on the bottom lobe of the
caudal fin, but the stripe separates just behind the dorsal fin and continues as two lines
over the back of the body. The colouration is also different, with melini
being a dirty white with black specks to the edges of the body scutes, while davidsandsi
has a tan colouration with no specks. If you can make all that out I will explain how
I spawned this species (C.davidsandsi that is ).

This picture shows the black stripe running along the ridge
of the back.
I purchased two pairs from different outlets and placed them in a 18" x
12" x 12" tank with aged water, pea gravel, Java moss, Java fern and a sponge
filter, but little did I know the problems I would have trying to spawn them, even though
one of the females was quite heavy. I fed them my usual; being flake food, tablets, white
worm, daphnia and bloodworm (live and frozen), and also undertook 50% cool water changes
twice a week, but I just could not get them to start. My usual visitors to my fish
house would come in and the first thing they would say would be, "have you not got
them spawned yet?".
This went on for three months until I decided to give them
one more try. I placed a powerhead in the tank for extra aeration and then carried out a
75% water change with part rainwater and flooded the tank with white worm. I then
locked the fish house and hoped for the best. Yes you know what I'm going to say - the
next morning I found a total of 14 eggs laid on the Java moss and Java fern. I
removed the eggs and put them into a small tank with water from the breeding tank . I used
light aeration, but three days later only four hatched as eight had fungused and two were
not fertilized. I had to go away for two days and I lost the fry due to not being able to
change the water. I needn't have worried though, for a week later they spawned for
me again. They laid only five eggs this time which I put into my small tank again, but
with no aeration this time. I also added meth. blue to the water.
C. davidsandsi egg
They hatched in three days, and after two days I started
feeding microworm as first food along with egglayer fry food. I did 50% water changes
every day. The next spawning was a week later, this time thirty eggs were laid. I watched
the spawning sequence this time which occurred at 9 a.m. One male chased the larger
female as they took up the customary 'T" position, with the male grabbing the
female's barbels with his pectoral fins and pushing her very hard. She then broke away
from him after about eight seconds, then she sat on her side for a further few seconds,
then expelled one egg into her ventral fins. She would travel about the tank with the male
chasing her for what seemed ages, before she would lay the egg usually in the Java moss
but sometimes on the glass. I noticed that the other male was trying to get into the act,
but the dominant male was chasing him away, so he would go and try to spawn with the other
female, but she was never interested.
I keep the fry in the small tank for two weeks, then I move
them to a seven gallon growing-on tank with a corner filter, doing water changes every
other day. This is when I start feeding brine shrimp as well as microworm and crushed
flake.
C. davidsandsi fry
This (out of focus!) picture is of an 11 day old fry.
They spawned quite regularly for me after that, with six to ten days between
broods. The other female is also producing now, so I am getting spawns of anything between
twenty and fifty eggs from the two pair.
For the record, the pH was 6.8 with the temp. being
80ºF during the day and dropping to 76ºF during the night in my fish house. The water is
very soft in this part of Scotland at G.H.l.
A lesson I have always learned from breeding Corydoras is
to have patience and plenty of it.
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