I think these are snappers. Notice the tails; they are fan shaped, not forked, nor lunate, nor straight. For a side view, look at the fish upper right. I apologize for the photo; I, too, wish it were better.
Photo taken December 4, 2007, Molasses Reef, buoy M2, Key Largo, Florida. 28 feet of water. 77 degrees Fahrenheit bottom temperature. This school of large (+/- two feet in length) snappers was barely moving, just around the corner from a large, barely moving Nassau grouper.
Do you know if it is a snapper, and can you identify the species?