@roscoeb, With only 12 shrimp you wont need to feed them much or very often.
Starting with twice maybe three times a week is a good idea. Drop in one piece of food and gauge how quickly they eat that up.
Variety is the key. Alternate the processed foods with fresh veg, leaves and you will do well.
If you leave a IAL leaf in there, the shrimp can snack on that at anytime. The Dennerle SK Protein should give them a good source of proteins, but you can also try frozen blood worms.
If you run out of ideas on what to feed your shrimp, check out the Food & Nutrition subforum.
http://shrimpkeepersforum.com/forum/forum/44-food-nutrition/