Blue ghost shrimp!

[Garrett.turbo]

couldnt tell yah sorry my fish fish gobble them up to fast

 

[muffywrx]

Someone already answered

 

[Rev_Jim_Jones]

I had about 3 dozen in a tank with no predators (well the red claw macro turned out to eat them when they molted), Diet seems to be the biggest factor in the colored dots enlarging. When they are eating Algae and scavenging they are usually clear with a light coloration, once they figured out how to grab food and run into caves with it the colors started picking up a bit mostly Green and Blue but others pop up occasionally.

 

[LGyure85]

Yeah, that makes sense. They LOVE fish food, so much so that they've learned to flip upside-down to get it off the top of the water. Sweet!