Ron,
Like Doug says, feed sparingly and test your water for nitrates often to see how much your feeding your tank can handle. I like clams better than shrimp or fish for nutritional value. But variety is better. I use mostly blender mush:
white fish meat
clams
oysters
shrimp
selcon
nori
throw in blender and shred finely. Throw it in a ziplock bag, flatten it out and freeze it. Then break of al little piece to feed. I feed about 10 minutes before lights out. That way the fish get some and the corals get the rest.
The most excited I've seen my corals get is with coral heaven from:
http://www.ipsf.com/
when my hands have grease/oil/dirt on them from working on cars, etc, and I don't want to get my hands in the tanks, I use DT Phytoplankton or bioplankton from liquidlife.
see:
Dr. Ron Shimek:
http://www.aquarium.net/0197/0197_4.shtml
http://www.aquarium.net/0297/0297_6.shtml
Having said all of that, shrooms and leathers should be able to get enough from the water and your fish feeding. When you get more corals, then you should look into feeding. Also, if I was going to do it again, I wouldn't mix leathers and SPS in the same tank. Too much chemical warfare and therefore water changes.
Good Luck!
Bill