So the bad news is my Wrasse is dead. I found what appeared to be what was left of a fish, in the very back corner of my rock. It had only been missing 2 days, but I'm sure my shrimp had his way with it. The good news is I found a dead spot behind my rock that had accumulated some nasty stuff. So i vaccumed it all out, and aimed one of my return lines at the dead spot (could have been part of my nitrate problem). The great news is I found my long lost Yuma stuck to the back of a rock! Stoked!
It still seems weird that a perfectly happy fish would just up and die all of a sudden...