They are very easy to take care of in an established tank. You need to keep a close eye on water parameters because they are very sensitive to ammonia and nitrates. Just like livebearers, RCS only need water and a mate to reproduce. . If you have fish in the same tank you'll need lots of hiding places that only the shrimp could get into. Mosses are great because they make good hiding places and the shrimplettes pick through them eating microorganisms until they're older.
There are other species of shrimp they can live with but there are others that they can crossbreed with. Most dwarf shrimp all have the same requirements so once you feel comfortable with the RCS you could add others! Here's the chart I use http://www.crustaforum.com/images/crossbreeding_big.jpg