AbstractEffective purified and unrefined diets have been developed and evaluated for use in studying the nutrition of lobsters (Homarussp.). A 4‐month growth experiment showed that the purified diets yielded weight increases nearly 80% of that achieved on a live food diet, with concomitant high survival rates. Lower‐cost unrefined diets supported growth over half of that observed on live food diets. Supplementation of a purified diet with an astaxanthin concentrate derived from crayfish waste enhanced growth significantly, and all the diets tested promoted growth and survival with only 0.2% dietary cholesterol.Growth and survival are the most useful criteria for evaluating crustacean diets, but other factors such as proximate analyses of feeds, physical characteristics such as pellet leaching rates, and measurable physiological effects can provide important supplemental information. Our analysis of some of these factors suggests that pellet integrity and resistance to leaching may not be directly related either to growth, or to levels of binder in the di