+1 to taking a very great risk in not covering the tank, especially with the prices some of these fish run at. Also +1 to eggcrate not being enough.
I lost 1 Pyle's to a completely uncovered tank, then 1 Pyle's, 1 anthias, 1 firefish, and 1 clown, to a hood that was not sealed up tightly enough. Not to mention, they had to get around the MH reflectors in the top of the hood and up at least 8" from the surface of the water to get out of the back of the hood. Last week, with eggcrate over my tank, I had dinner interrupted when my cat brought me a piece of fish jerky that was, that morning, a very fat and happy male Pyle's. I'm just happy he didn't eat the fish!