I have copepods in my refugium and these bug like creatures don't look like them. My Mandarinfish won't eat them he swims right over them. What could they be. Could they be the ones hurting mt Derasa Clam? Sorry such a bad pic.
Don't think we can ID them without a better picture. Can you maybe siphon some out in to a small container and see if you can get a better pic? How big are they? Can you see legs or any other structure?