"El Scorcho" wrote in message oups.com...
they look like miniature grains of rice or tiny maggots.. nasty.

these could be isopods, amphipods copepods and more other things
Compare images below and try to match what you see with the proper name.
http://images.google.com/images?q=is...&sa=N&filter=0

what can I do to get rid of these?

before you try to rid of them make sure they are not good for the system.

because of a calcium overdose most of my fish died,
I only have a yellow tail damsel lef, of all things..

Just curious, but how did you overdose calcium to kill all fish ?