I say rarely feed live, due to the fact that feeder fish like rosies or goldfish or any of the others are high in thiamine and low in nutrition, goldfish are also high in ammonia and fat, as well as their scales are difficult to digest. As far as feeding ghost shrimp, imo it should be as a treat and to wean them onto frozen food. But as to why not is because unless you feed them yourselves and "gutbust" them they tend to be devoid of nutritional value. just my optionon