Roz, I would try establishing a fry tank for the eggs. My first time seemed to be quite successful. My corys are on what seems to be a monthly breeding cycle. The last time the big mom started laying, I was ready. The eggs (well over 100) were collected and placed in 10 gallon fry tank about half full with water from the fish tank.
There's no gravel in the fry tank. There is a heater and an underwater sponge filter. The sponge filter keeps the water moving to prevent bacteria from forming on the eggs. The sponge filter is INSIDE a breeder net. It sounds odd with fry on the outside of the breeder net, but without this configuration, the fry would be sucked into the sponge filter and die.
On about the fifth day, over 100 hatched! I was expecting 15-20, so this is a bit overwhelming. A handful have died in the couple of weeks since hatching, but I still have nearly 100.
After the first few days, I started feeding them a mixture of algae chips and tropical fish food (nothing exotic) that I ground fine in a spice grinder. I will keep them in the fry tank for a couple of months until they are big enough to not get eaten with other fish. Not sure what I will do with most of them. I will check with local pet stores, offer them to friends, or advertise on Craig's List! I didn't want 100 extra catfish; I just wanted to see if I could breed successfully. Good luck!