What is a diamond white gourami? I have never heard of something like that. Did you find that name in your LFS? Maybe the name you are actually looking for is moonlight gourami, which is pure white/silver colour. Only thing I can match up with the 'diamond white' nickname.
Well when I looked it up on google, and it gave me a pic of a pearl gourami which has many names including white diamond. Other then that they are an awsome fish I even have them ,"soon getting more", they are very coloful and are my favorite gourami. Besides that I think you'll find alot of information on them.
