I think if you were to have dwarfs, they would have to be in pairs (1 male to 1 female) in a 15 gallon tank minimumally.
Dwarfs are closely related to bettas so they should not be added to the same tank. Remember, dwarfs are semi-aggressive, so research tankmates carefully before adding.
FireOasis - 3g
Zachary the Halfmoon Plakat
CichlidHaven - 55g (under construction!)
0.0.7 Black Widow Tetra
1.0.1 Convict Cichlid
0.1.0 Firemouth Cichlid
HermitBase - 10g
Zephus & Monoculus the Purple Pinchers (Coenobita clypeatus)
x1 Convict Cichlid Pair (actively breeding)