I feed them this:
Liquid Life BioPlankton can achieve the beauty and diversity of a reef by providing the planktonic life that is absent from aquariums, but essential for the development of a marine food web. Fish, Zooplankton, Filter Feeders, and Corals feed on plankton either directly or indirectly. With an average cell count of 10 billion cells per mL, a size range of 2-16 microns, and a broad nutritional profile, BioPlankton results in enhanced species diversity, density and reproducibility.
Fish only, or new reef, 1 pump per 60 gallons every other day. Aged reef 1 pump per 30 gallons daily. Mix in saltwater prior to use. BioPlankton can be used to enrich rotifiers and artemia. University tested, aquaculture proven, hobbyist approved
So I guess it alive