Hi,
If you do not have a breeding tank you can use a jar - I would get rid of the clay pot and use an ~artificial leaf~ made from a green plastic container that you can cut to your desired shape for the fish to deposit eggs on(has to fit the jar that you will be using); after they deposit the egs on the ~leaf~ just slide it into the jar and seal it - you can improvize a top from a piece of fine net fixing it to the jar with rubber bands; the sealing top needs to have a tube size hole in it as you will have to introduce an air stone into the jar for proper aeration and water ventillation; the airstone has to provide fine bubbles so the air can leave the jar through the net; the jar has to be fully submerged into your tank this way you do not have to worry about temperature fluctuations; as Jason said at the begining the young parents are just learning parenting skills and this is valid for eggs fertilisation too, so do not be upset if for the first few times only a few from the initial number of eggs will hatch - the eggs that are not fertilized will become white and they have to be removed(I would not recomend this though if you did not do it before) or they will cause fungus - instead of removing the unfertilized eggs, you can add methylene blue into the jar( you can find this usually at any pet store - please read the instructions when you buy it) to keep the fungus under control until you will have fry - you will probably still have fungus but it will be somewhat contained until the fry can swim and you can remove the unfertilized eggs safer.
Before the fry can swim they need no food, but they will be ready to eat as soon as they swim, so you will have to be prepared for that - the best results I had food wise is using artemia salina(brine shrimp) - you can buy unhatched eggs of this crustacean at your LFS and just have to follow the instructions how to hatch the eggs(it is verry easy...).
The fry can live in the jar for several weeks - if the jar is big enough even for a longer time - as you do not have to move the pair with the eggs, a 10 gal tank( depending on the number of baby angelfish that you will have) can be used to raise the fry - if you have more than 50, a 10 gal would not be enough to bring them to the size the other fish would not be a threat.
I hope this helps you somewhat, and I wish you luck
