This might sound like a funny question, but I would like to know...could color have an effect on a fishes health? The reason I ask is this...In my wife's guppy tank, she had 5 males. 3 are yellow and 2 are/were blue. The yellow ones are fine and happy, the blues seem to have expired before their time. I did a quick post-mortem on the fish, and saw no fin problems, spots, anything to suggest disease or aggression by the others. Any thoughts? ???