Sudden Appearance of Shrimp-like Zooplankton

[Kates]

Hi, I believe I have some kind of tropical zooplanktonic (is that a word?) crustacean. I will post pics ASAP this afternoon: I was changing a piece of Live rock from my refugium to my main tank last night. I rinsed it with tank water briefly to get off any debris... Then I noticed something strange in this rinse water - tiny floating/drifting crustaceans, about 4-5mm in length. I had already put this piece of rock in the main tank, and when I looked in the tank, these things were ALL over! They were drifting mostly at the surface of the main tank, and in the bowl. Very shrimp-like in appearance, in fact they look very much like tiny krill only they are not strongly colored. Noticeably pointy "nose" and large eyes. Occasionally flip tail segment which curls to about the length of the front end "carapace".They mostly drift but can position themselves somewhat, and can move smoothly backward, almost like a squid. They rarely flip their tales, but just propel themselves backward, usually with their tale up at an angle and head facing down. Seem to readily eat phytoplankton when given. Very attracted to light sources. If anyone has seen these before I'd like toi know what they are, and if they are culture-able, since I'm currently starting a culture of copepods. As I said, they look very much like krill, and if I could keep them in any abundance I bet they would be a good addition to my mandarin's diet? Thank you in advance!

[cloak]

Mysid shrimp maybe? Check this out.

http://reefkeeping.com/issues/2004-02/rs/index.php