By dwarf croaking gouramis do you mean Sparkling gouramis? I believe they are the same thing, if not ignor this..hehe..
I have 2 Sparkling gouramis in a 10g, they might actually be a pair. They are great young little fish. Don't bother anyone, and are very bright! Their eyes just sparkle....They are excellent fish and I was told that although they still have some, aggression is not as big a problem between males like in their larger counter parts.. If you have the facilities, I'd say go for it!
PS-They love brine shirmp!