We have our Sparkling Gourami in a two foot community tank with a range of Tetras, a lone Dwarf Gourami, a Chocolate Gourami, three Corys, and couple of Hillstream Loaches.
It has a PH of around 6, temp around 25 deg.
It is a heavily planted tank, in fact, rather over planted, and has a large wad of Java Moss that covers about two thirds of the water surface.
We maintain a popluation of somewhere around eight Sparking Gourami in this tank of varying ages. We usually have one adult die every six months or so, but they breed slowly to replace the losses.
We also have three in another tank, the oldest of which thinks he's a Blue Ram, and would rather spend his time hanging around with the Rams, than the other Gourami!