I made a post about this a while back, but I can't find it.
I have a 20 gallon Long with several flame gourami. (I started with a pair, but now I don't know how many I have. It's at least 7.)
The tank has relatively low light, and the surface is nearly completely covered in duckweed. It has several pieces of drifrwood, along with java moss, a tiny E. Parvula, a couple crypt wendtii, dwarf sag, a big dwarf water lily, and some floating elodea.
The tank isn't thickly planted, but its got a lot of driftwood.
My only complaint is that I never really see my gourami- any movement in the room sends them darting for cover, they won't even eat unless I move away and sit perfectly still.
I've heard that dither fish will help. Rasboras are the obvious choice, but Tetras are always on sale at petco. Are there any tetras that will come out at feeding time but won't terrorise the gourami?
If not, I guess I'll have to go with harlequins...