I have had an Asian Knife (albino) for about 2yrs and he appears to be healthy. I feed it frozen bloodworms as that is the only food he will consume at this point (and I have tried tubifex worms, frozen brine shrimp and flake.) Do I need to be worried that this diet is too one-dimensional? Is this fish getting enough nutrition or should I be experiementing with other types of food or adding supplements to his present diet? Thanks for you help!