Sick Gourami?

[FishSurf]

I have one dwarf gourami in my 20 gallon tropical community tank along with 11 other fish. It is a non-planted tank, and I keep the temperature at about 77* F. I do regular water changes, and feed them twice a day. 
 
I have noticed for a while now, that my gourami hasn't been eating very much, if at all. Every time, I feed my fish it just swims around in the same place, and may occasionally take a bit of food in its mouth and then spit it out. This has been going on for a while, so he must be eating something because he is still alive. However, a few days ago I noticed that he is a bit off-color and is swimming strangely. Sometimes he just floats a little sideways at the top, and sometimes he swims normally in the middle. All of my other fish seem just fine, so I doubt it is poor water quality that is affecting it. His poop is clear and stringy as well, not like the brown of my other fish. Any ideas?

 

[BerryAttack]

what other fish do you have in the tank?
should only feed once a day, even though you do regular water changes (once a week 15-25%) it'll affect the water.
how long have you had the tank set up for
it could be the gourami is stressed and possible over crowding (don't know what fish you have) most likely its an internal virus. or it has the gourami sickness, which it'll die and you can't do anything to stop it.