i have a Bangaii Cardinal who used to tear through the Mysis shrimp at feeding time. Now he is not eating hardly at all if any for the past 4-5 days. Should i be worried? he is not showing any physical signs of disease. I was thinking about going out and getting some frozen brine with spirula (sp) to maybe give him something different. He lives with a Yellow Tang, 2 clownfish for the moment in a 125G tank. any Suggestions?