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