Corydoras Catfish

There are a lot of ways to spawn corys. I have seen people with incredible results with bare tanks. It just never worked for me. I had pretty much given up with 6-7 cory aeneus and put them into a 10 gallon tank that I was growing a couple of small swords and a lot of pygmy chain sword. This tank grew to the point that it was nearly impossible to see into the tank. (This is the tank on the home page). Then the corys started spawning all over the place.  When I thin out the tank they stop spawning until it gets really thick again. The metae's were the same way. They were in a 29 gallon tank that was completely covered for 4-5 inches across the bottom. I was using the tank to grow out some platties. I noticed the platies chasing the corys all over the place. What was happening is the corys were spawning and the platies were gobling up the eggs as fast as they were laid on the glass.

With these two events, I have only set the corys up to breed in heavily planted tanks. What follows is definitely not the only way, probably not the best way, but it is a good easy way that works for me.

I keep:

        Corydoras aeneus

        2-3 month old fry, click for larger picture

        Corydoras metae    newborn pic

        Corydoras paleatus sp Albino    spawning pic

        Corydoras paleatus  the youngsters pic of Corydoras paleatus albino. These are very iridescent

        Corydoras panda  These are wonderful. Keep them in at least 6 fish to the school. They stay very tight together as they swim around.

        Corydoras melini

        Corydoras adolfoi

        Corydoras rabauti

        Corydoras schwartzi

        Corydoras Blochi Blochi

        Corydoras aeneus with the orange fins

        Corydoras 2 species that are unidentified.

They are kept in 5 to 10 gallon tanks. Many of them spawn on a regular basis. For me the key to spawning is a very small gravel and sand substrate with a lot of plants. The tanks are full of crypts, java fern, and pygmy chain sword. The thicker the plants seems to make the more often they spawn. Their basic diet is frozen brine shrimp. This is supplemented with Sera O-nip tablets, cut up earthworms, and live blackworms.

Even when I am sure that I have males and females, spawning is a lot easier with 6-10 fish in a group. There just seems to be a group psychology or hormonal thing in the water that gets them going. Of course with this many fish, spawns commonly run in the hundreds of eggs (PIC).

Spawning is almost assured for me with the following:

Tank temperature is room temp, floating between 66 and 72 degrees.

Feed lots of live blackworms for 3-4 days.

Do a 40-50% water change with slightly cooler water.

They will spawn in 1-2 days, covering the glass with eggs.

I let the eggs stay on the glass for at least a day. This seems to remove some of the stickiness of the eggs and let them harden up. Then I use a razor blade and scrape the eggs off the glass. The eggs are put into another container, usually a plastic shoe box, with water from the tank, an airstone, and a really thick mat of java moss. The eggs are slid off the razor blade onto the java moss. This goes a long way towards keeping the eggs from fungusing since they have water circulating.

The eggs in hatch in 3-5 days. It will be a day or so before they are ready to eat. The java moss bed they are hatching out on provides plenty of food for them if they are hungry before I start adding micro worms and vinegar eels. I feed this for at least a week before starting to add very small amounts of baby brine shrimp. While the baby brine shrimp is a critical food, it is always the most critical time for me. Left over shrimp spoils and funguses and will wipe out a hatch in a day or so. I lost many batches of eggs after getting the fry up for about 2 weeks. Just about the time they were big enough that I was starting to relax, they would all get sick and die. Adding the thick java moss and feeding the micro worms for a longer period of time seems to have solved that. (PIC).

When the fish are about a month or so old, they get floated into a 10 gallon tank, still filled with java moss. (PIC). They are sensitive to fresh water so I syphon water from a tank beside them for water changes. I take a 10-20% of the water out of their tank, then set up a syphon to the next tank that has only a few cats in it. I refill the second tank, wait a day, and syphon more water over. Works for me.

10/1/2003 Breeding update. Thanks to Eric Bodrock who came to speak to our fish club on catfish. The man is a genius. He gave me the big key to hatching cory eggs. Darkness. Wow. I have had 3 spawns in the last 2 weeks. Each time I put the eggs into a plastic shoe box, touch of methyl blue, airstone, then a towel over the whole thing. Really cuts down on the fungus and velvet on the eggs. All three batches have to be close to 99% hatch. And a week later, nearly all the fry are still trucking around. I started them on microworms. I am now adding some baby brine shrimp. The tubs are still mostly covered with the towels, insuring only a little light is getting in. I am slowly exposing to more light as the fry get larger.