Once we got here, the fish had to stay in the small tank until a guy came to "uncrate" our big tank. A day or two before we were able to move the fish into the big tank, I told Shawn that I hadn't seen the Ghost Knife in a couple days. I didn't think this was a huge deal...he likes to hide in the rocks and the castle in the tank. Shawn decided to look for him, and he removed the big rock where the fish normally liked to hide. No Ghost Knife. Shawn then turned the rock over...and found the fish. Dead. The Ghost Knife, for whatever reason, had managed to wedge himself into a hole in the rock that was much smaller than he was. We obviously don't know if the thing suffocated once he got stuck, or if he freaked out and gave himself a heart attack, but he was very definitely stuck in the rock, and very definitely dead.
So after all the trouble we went through to get him here, the dang Ghost Knife goes and kills himself in the tank. Stupid fish. At least this one didn't commit suicide by jumping out of the tank while no one was home (like another Ghost Knife did at Shawn's old house a couple years ago). And the rest of the fish are now happily swimming around in the big tank, with clean water, brand new gravel, and even a nice new filter and air pumps.