Blonde Guppies, Gold Neon Tetras, are the two first yellow community fish that jump to my mind for yellow friendly fish. If you are willing to take a risk, there is also the possibility of adding a yellow colour morphed Betta (you'd have to watch to make sure the Betta doesn't get picked on too much by the tetras though since tetras are known fin nippers). If not any of those, you could look at Blue Eye Forktail Rainbow fish.
Walking on Sunfish, WhooOOOOooo. I'm feeling good.