Hi,
Rams are usually best if kept as a male and a few females. The females will require a territory of around 1 cubic foot to feel at home, so if you have a standard 2 foot tank, one male and two females will be fine, one male and three females for a three foot tank etc., etc....
The male will patrol his females' territories, and they will keep themselves apart with the odd border dispute to spice things up - very entertaining!
Marc