It has been many years (like, over 30) since I spawned angels but some of what I did is still relevant. I cannot remember how long the newly-hatched brine shrimp survived in the tank, but if you see dead shrimp lying on the bottom I would siphon them out regularly as the angelfish are unlike to eat them and they can pollute the water. Don't feed too many at one time, so most get eaten fairly quickly. Multiple feedings are better than one larger feeding with any fry.
I also weaned my fry off live foods as fast as I could. Grind up some good quality flake food with your fingertips into a fine powder, and mix this in a small container of tank water until it is water logged. Then use a pipette to squirt some close to the shoal of fry. As with the shrimp, more feedings with less is better. I believe I started this once the fry were free swimming. There is good nutrition in the flake foods.
Another trick I know now but didn't back then is to place some dried hardwood leaves in the tank. Oak, beech, maple work well, or you can buy almond leaves in some fish stores. The leaves must be completely dead/dry. They will float at first but then sink, and are an excellent source of infusoria which is ideal fry food. Tests have shown that fry in tanks with dried leaves develop considerably faster than without the leaves. The fry will nibble the live food off the leaves.
Byron.
