Digital Camera Aquarium

What is this animal? It was found in a 10-gal cherry shrimp aquarium and is barely visible to the naked eye.?
Under light it increased its speed.
Go to http://i6.photobucket.com/albums/y244/tota107/Fish%20Tanks/Closeup3.jpg to see a picture. It appears to have antennae and maybe a couple of flagellates at the rear.
At http://i6.photobucket.com/albums/y244/tota107/Fish%20Tanks/Withpintip.jpg is a picture with a sewing pin so that you can have an idea of the size of the creature.
One more picture can be seen at
The pictures were taken with a digital camera and a very good magnifying glass.
I would also like to know if the animal is harmful to aquatic plants, shrimp, fish, or snails.
What does it eat?
It’s a copepod. This is a very large class of crustaceans, many of them are marine. The one with the two big round things is a female. The round things are clusters of eggs. Copepods eat small microscopic plants and animals. Many marine copepods are parasites of fish. The one in the fish tank is a form of freshwater plankton.
baby GOLDFISH planted aquarium tank TAKEN WITH a PowerShot A720 IS Digital Camera