Hi Lyre Tail,
had a similar problem with our heater. Took it out of the water briefly to rearrange something in the tank, and you know how it is when you get sidetracked. The next thing I knew I could smell something like melting plastic. Guess what? It was! The heater was touching the air intake tube for the filter. Remembering the heater was out of water my first reaction was to immerse it back in the tank to cool it down, not an unreasonable idea you might think. BIG MISTAKE, the thing exploded!

To compound matters it was our first zebra pleco and we had had it less than 24 hours!!! Fortunately he was fine and seemed to suffer no adverse effects.
We also had another problem with some decor in the tank. We placed a cave network in the tank which we had bought previously for our community tank, thinking it would be ideal. Again BIG MISTAKE! He liked his new cave network and soon swam in. I got up one morning to check everything was fine, and found him in an unusual place at the back. Thinking nothing of it I carried on with my tasks for the rest of the day. However, everytime I did come back he was in the same place, but not having moved so much as a fin. So when the end of the day came I decided to check on him. I nudged the cavenetwork slightly, no respone, I tried again. Still no response. Yea, my heart started racing

. I quickly picked the cave network up and he still didn't move. I had a closer inspection only to find him wedged in one of the contours of the cave. I tried freeing him by holding his sides and gently trying to juggle him loose, he wouldn't budge an inch! I tried breaking the cave thing open but only managed on snapping a little bit of plastic off. I tried again with a little more force, another bit of plastic came off and I banged my forearm on the tank. Third time lucky, I gave it a big tug and snapped enough off to free him, but gashed my finger on the jagged plastic! I still have the scar to this day (although my girlfriend says I'm imagining it lol). Luckily he again escaped death and was fine.
It made me think that fishkeeping is more of an extreme hobby than most might think lol. I have been thiinking of calling the fish in question Rambo lol.