Last time I went on a 15 day vacation I asked my roommate to feed me fish.
When I came back everyone was alive and the tank looked great.
"Thanks for feeding my fish while I was away." I told her.
"Your FISH!!! I completely forgot about them..." she replied.
Never know what can happen when you go out of town. Accidents always happen. Sorry about your fish. No way you could have known the heater would explode.