Copepod sp.

Copepods

Taxonomy:

Kingdom: Animalia

Phylum: Arthropoda

Class: Malacostraca

Order: Calanoida

Family: Calanidae

Genus: Copepod

FYI: These small, usually 1 mm or less, white or somewhat transparent crustaceans or "bugs" makeup about 90% of the zooplankton in the oceans. Most of the 8000 or more species are beneficial and feed on detritus and plant matter, e.g., microalgae in the wild and aquarium. In turn, fish feed upon them. In the aquarium they are mostly seen on the lower aquarium side panels or sand surface areas. Most are free living, however, there are some parasitic copepods that use their anchoring appendages to deeply penetrate flesh and can cause severe tissue damage. Yet, parasitic copepods are very rarely seen in home aquariums.

Generally, copepods are considered an excellent live food source for small fishes, e.g., damselfish, mandarinfishes, wrasses, and small angelfishes. Since they feed on detritus and microalgae, they can somewhat help keep unwanted algae blooms in check.

Often can be seen with the aid of a flashlight or moonlight after the regular system lights go out. Those seen in the photo are in my aquarium, and the green one is green because it just finished eating some green microalgae!

Their appearance in the aquarium should be considered a highly beneficial situation.