If you are successful, you can get 80% to survive. They don't need daily water changes (although it is a good habit to get into).
Once you get them to the 3 week mark, you're pretty much golden. Just feed them, do a weekly water change, top off the water, just routine stuff.
Once the clowns hit the 1 week mark, I usually put a baseball sized rock in the tank with them. This gets loaded with bacteria and really keeps parameters in check.
You have to raise phytoplankton to feed rotifers to feed the baby clowns. Some people have had good success not feeding baby brine shrimp. You can go right from rotifers to crushed up Otohime or crushed formula 1 pellets (what I use).
Check out the breeding forum here on RC. There are a few threads there that explain a lot. They are breeding logs of rkelman and FB. Also, consider picking up the book "Clownfishes" by Joyce Wilkerson. It is pretty much considered the Bible of clownfish breeding.
Good luck raising babies. It's fun and you learn a lot.