Steve,
The Blennies in our holding facility are currently being fed Spirulina enriched brine shrimp to encourage wild harvested fish to eat in a captive environment.
Once acclimated to your aquarium the diet of the Blenny should include vegetables, such as frozen and dried foods containing different types of algae. The Blenny is a natural grazer and it is important to maintain them in an aquarium with plenty of live rock. The live rock will offer the Blenny some natural food sources as they feed on algae and other food sources provided by the live rock.
We wish you much success on your new arrivals and hope your algae concerns are soon resolved. If we can further assist you please feel free to contact us.
Joyce F.
LiveAquaria
Drs. Foster & Smith