I received 5 blue reef chromis yesterday an as of last night one was missing, I thought I'll give it a break to adjust to a new tank. Well, as of now, no chromi still, all others are out and about eating well. All my pumps intakes have a net, so it didn't get sucked in. I have no other fish or inverts that might have ate it. I moved the rocks and re-aquascaped----no chromi. I looked around to see if it had jumped out---no chromi. All parameter are 0 except for nitrates which are 15ppm. What in the world??!!