Catfish eggs

Question
Greetings--I reviewed the questions and answers  about Corydoras egg-laying, but can't figure out what's going on in my tank. I have two catfish in my 30 gallon tank (yes, just the two catfish, don't ask) and there are lots of eggs affixed to the tanksides. The eggs have been there for about seven days, and they have no sign of fungus--they look clear and clean although some eggs seem to have a dark spot inside. Are these fertilized eggs? If so, is it possible some have hatched? I don't see any little wigglers. (I did install a filter bag over the filter intake, just in case.)  

Answer
Dear Sheila,
Congratulations on the Corydoras eggs! Depending upon the species, some Corydoras eggs take about a week to hatch. Many aquarists remove the eggs from the main aquarium to save the wigglers from the sometimes hungry larger fish and this can be done with a careful hand and a razor blade. The falling eggs can be caught in a net and place in a small aquarium or container with the original tank water. Most Corydoras eggs are white but sometimes you can see some development in them. The dark spot that you are seeing could certainly be developed fry.

Once the babies hatch you can feed them with Microworms or newly hatched brine shrimp---even frozen.

Well, I really hope this helps! You could have some cory fry that have already hatched,they might be hiding in the aquarium or could have gotten snacked on by the larger catfish. But you should be able to get a few babies if you remove the eggs to a safe container. I wish you the best with them!
Karen~