Cyclops Copepod (water Flea), What are Theyand are They Dangerous to Fish or Fry in an Aquarium?

QUESTION: I have these bugs in my aquarium;Cyclops are generally eaten by Phantom Midge
they are very small about 2-3 mm long with oneLarvae and water mites.
black eye in the middle of its head. It is grayish inREPRODUCTION:
color. It goes jerking through water in ratherThe female Cyclops carries her eggs at the back
spastic motions.of her body. There are fewer males than females
What are these?present in the population, and the males are
ANSWER:smaller. Females are often observed while
It sounds more like this, which is a Cyclops (aswimming to have paired egg sacs, and most of
type of copepod); they range in size from 1-3the species are capable of explosive outbreaks
mm. It is called a Cyclops because of the singlewhen the water temperature and other conditions
eye spot. This female carries two packages ofare optimal.
eggs near the base of her tail.CONCLUSION:
A little about Cyclops;Cyclops can also be intermediary hosts to the
HABITAT:Guinea worm (which affects humans, but not
Cyclops live in freshwater, such as ponds andgenerally fish) and fish tapeworm. These are rare
lakes. They prefer areas of still water with a lotoccurrences for the Cyclops, and many aquarists
of algae.consider them valuable as a fish food and even
THEIR PLACE IN THE FOOD CHAIN:sell them. I would not be overly concerned with
Cyclops are omnivores; they eat algae, smallthem for most aquariums as long as good
animals, detritus but not usually fish. But weak fryaquarium cleaning methods, such as vacuuming
MAY be harmed by these copepods. Someare practiced. The exception would probably be
species of Cyclops are not free-living, existingwith fish breeding. In this case, vacuuming gravel
instead as fish parasites, but these are notand rinsing off live plants in a mild bleach solution
common. Tropical and native fish enthusiasts utilize(live plants can handle a 25/1 solution provided it is
the cyclopoids as a high protein live fish food,rinsed off) would be in order. Keep in mind that
especially for immature fishes, and in a fair twistthese copepods do not like areas of high current
of fate, some Cyclops species have been foundand do like a lot of algae, so changing these
feasting on larval fishes, particularly in fishconditions would go a long way in controlling
hatcheries.Cyclops.