The new stock, nearly all males and smaller than members of the original colony, were housed in the Corydoras stock tank. By late August all the new C. metae were looking really good. Three males were seen pursuing one fish around the 100cm tank. Perhaps this was a female, but there was no sexual characteristic visible. I decided it was time to move the six smaller fish (now 38mm) to the breeding tank containing the original C. metae (which still had not spawned).
September 23rd 1981
After a few weeks in the breeding tank, three small males were seen following a large female. This did not seem to be the start of spawning, as the fish were leisurely compared with the normal spawning behavior of other Corydoras. At feeding time on the following evening a large egg was seen attached to the leaf of a plastic plant. On closer examination, more large eggs were found individually attached to the roots of the Java Fern and on some leaves of the plastic plants. The plants and eggs were removed to a 25cm x 15cm x 10cm tank filled with half fresh and half spawning water, with some gravel and a sponge filter.
After five days at a temperature
of 75°F, twelve eggs hatched (eight had been removed
after fungusing). Liquifry was added to the tank on
the second day and thereafter brine shrimp, micro worm
and prepared fry food were fed regularly. Despite an
abundance of these foods the fry did not appear to be
getting any nourishment. Their stomachs did not seem
to be full at any time and they started dying after
three days. By the third week only eight fry survived,
but all were looking much healthier, with full stomachs.
During this critical period the bottom of the tank was
siphoned every day and topped up with aged water of
the same temperature. This kept the tank very clean.
Again, I had the same difficulty feeding the fry. By the end of the first week ten fry had died, no matter what was fed (including liquefied spinach) their stomachs was never full. It was not until the fourth week that the deaths stopped. The growth of the twelve fry was very slow, but at six weeks they were moved to the tank containing the first spawning of C.metae, which were now twelve weeks old. Both spawnings continued to grow and to date all are the same size.
This article first appeared in the Catfish Association
of Great Britain Newsletter !982