Breeding Corydoras pulcher Isbrücker & Nijssen, 1973
There may be no other Corydoras that is so often misidentified than Corydoras pulcher. About half of the pictures on the Internet show the wrong fish. Misidentifications occur with some of the several forms of C. schwartzi (which is living in the same area, the Rio Purus), but also with C 141 and others. For correct pictures refer to (Fuller & Evers 2005). C. pulcher is a big (7-8 cm) Cory with an elongated white first dorsal spine, a long snout and a longitudinal body pattern.
When I had the possibility to obtain ten adult pulcher, I had no reason to doubt that transporting this species would be a very unhealthy thing. They are very fast and ran against the glass when catching. In the bag they swim against the plastic film and get bloody snouts.
My ten pulcher turned out to be six real pulcher and four others, of which one is not identified until today. They were living more than two years in a community tank with several species of Rainbow fishes.
In November 2004 I moved one female and two males in a 60x30x30 cm Tank. After living two years in feeding concurrence with fast-eating Rainbow fishes they were used to hunt for their food and for sure not overfed. Now they received plenty of good food (frozen Bloodworms, Black worm and Tubifex, live Grindal worms) and it took only a few weeks to see the female becoming much wider with a big belly. I made Water changes twice a week with 30-40% of cool Rainwater.
There were no signs of the typical nervousness when Corydoras are going to spawn, but two weeks later I found that they had already spawned during the night. I have never seen such a Corydoras spawn! The eggs, about 150, had been deposited similar to Cichlids all in one place on the bottom glass of the tank, in an area where the Glass was free from Sand. The parents were sitting close to the eggs, it seems as if they would watch them. The eggs were adhering very tight to the Surface, but I collected them and put them in a hatching tank.
I am sad to say that the eggs were not fertile. They were all fungused in one day and deteriorated. I felt my dream of breeding pulcher had been gone.
But two weeks later they spawned again! Same behaviour, same place. I took them out and put them into the hatching tank. This time some larvae were hatching, but died after a short time. I had a few eggs for “photo-shooting” in a little plastic shell and those were hatching normally and I could obtain one viable fry from that. Anyway – a first success!
Big surprise – they spawned a third time! This time I had lowered the pH in the breeding tank and in the hatching tank by adding some more Alnus cones than usual. That turned the water browner. This time the hatching was better and in the first few days of January 2005 I could see here and there the odd larvae in the gravel. Once I saw that they had absorbed their yolk sac I started feeding Micro worms and could see them eating.
All together I managed to raise a total of 26 fry. Compared with an estimated 450 eggs this a very bad quota, but it is a first success. I will keep on trying…
Literature:
Ian A.M. Fuller & Hans-Georg Evers: Identifying Corydoradinae Catfish. Ian Fuller Enterprises, ISBN 0-9540872-2-4
