My 2 M&F honey dwarfs are currently housed with 5 neon tetras, 2 coryadora, and 3 otocinclids, no problems from them. though I'm not sure exactly how regular dwarfs act. currently housed in a 20 US gallon.
Gauramis need special conditions to spwan, lower water levels, floating plants, low current at the surface, lots of hidy holes for the female, then if they do happen to spawn, the female should be taken out quickly, the male takes care of the fry, then once the fry start wondering about you take the male out too.
but were trying to avoid that so if you want, keep the water level close to the surface, and keep a nice current going at the surface, that should stave thigns off.
FYI, My honeys have taken to trying to bring plants to the surface to slow the current down, I think.