Tigriopus californicus is a copepod of the harpacticoid family. Tigriopus californicus are pelagic, i.e. they swim in the water column unlike benthic copepods which live on the substrate and in living rocks. For this reason, Tigriopus californicus is an excellent copepod for feeding all types of fish. However, because they are pelagic, they will not colonize live rock. Fish will feast on these copepods.