Sick Dwarf Gourami: Help!

[Fisharefriends84]

My Dwarf Gourami is very ill. He is usually moderately active and now he is pale and extremely listless. He seems to have trouble swimming to the surface during feeding time as well. None of my other fish (5 diamond tetras and 8 neon tetras) seem to have been affected by whatever is ailing him. Could he have a swim bladder disorder? I'm really concerned because he looks like he's in terrible shape. I'm open to any other ideas that anyone may have.

*Additional Info
He is in a 20 gallon planted aquarium. Right now my nitrate levels are 10mg/L, my pH is about 6.6, my nitrites are at 0 and my ammonia is 0 mg/L. The water was just changed (30%) As far as the fish's physical condition, he is not showing any change in appearance outside of coloration. He is pretty pale right now. I'm not sure if it is Gourami Disease because I've had him for about a year and he has been healthy up to this point. He has been showing symptoms for a couple of days now. I hope this info helps. Thanks all!

[BillD]

It is possible the fish is nearing the end of it's natural life expectancy. Many of the smaller fish have short lifespans. It sounds like you are doing things right, and the test numbers are good.