Tank Talk Magazine June 2011 | Page 11

Breeding corys The first corydoras I bred as a teenager was Corydoras aenus – the bronze corydoras. It wouldn?t be a big stretch to assume that this could even be the first catfish that many of us kept based on advice from the local fish store that “they will clean up the bottom of the tank for you”. Sound familiar? Depending on finances many of us probably bought perhaps just one or two fish and didn?t think about keeping them in a school. My first attempts at breeding bronze catfish went surprisingly well. I found that by feeding the corys up on white worms until the females got fat, doing a 75% water change with cold water and then generating heaps of water movement with pumps and airstones I could get them to spawn. I was able to do the same with Peppered Catfish (Corydoras paleatus) and Corydoras trilineatus (often misdescribed as Corydoras julii). I am pretty sure these are the easiest of the corys to breed. You can tell when corys are ready to breed as they get very active. One or two males follow a female around the tank and they form a T shape to fertilise the egg. The resulting eggs or eggs are then held between the ventral fins of the female who then searches for a site to deposit the eggs. The eggs are usually deposited in areas of strong current or in the top third of the tank , mine usually place most of the eggs in floating plants that are being circulated by the current or very unhelpfully in the top back corners of the aquarium. Corys in breeding condition are easy to sex , the male is almost always much slimmer and smaller than the female and the female will be noticeably broader around the middle. This difference is most pronounced when viewed from above or behind. I fed the resulting fry up on microworms and powdered flake food and it all worked out pretty well. In no time at all I had schools of 20 or 30 corys of different types all swimming around and that was when I realised that was how corys should be kept. In fact if you want to see corys in the wild have a look at the video we posted on the CDAS Facebook page where you can see they swim in schools of many hundreds. CORYDORAS STERBAI EGGS