What's the biggest mistake you've ever made?

Keeping with the Python accidents:

I have over flowed my 75 gallon, getting distracted playing with my son when I was refilling it. I suddenly heard water spashing, and set him down so fast it scared him. Nothing to major, but I did have an hour's cleanup!

Much worse, I had a friend who did this with his saltwater tank. He use a python to fill it up, and just mixed salt right in. I know this isn't the recommended way, but he had been doing it like this for years with great success. Anyway he forgot about the water change, and just left the python running. This washed all the salt water out, drained the hot water tank, and filled his tropical salt water tank with cold fresh water. When they remembered and went to look all the fish were stiff and floating on the surface, some of them were over 10 years old in his tank.

To top it off, he was actually moving, and was in someone elses house while finishing his newhouse, so he flooded out half their house with salt water! No fun at all.
:mad2:

He still hasn't setup again. On the plus side, he has lots of equipment he lets me use for free now!!!
:thm:
 
Ooops! used a styrofoam cooler to park my excess plants & it wasn't quite waterproof. Cupped hardwood floors, OMG! Hubby just shrugged it off, he's wonderful that way.
 
when i was little i decided to 'help' my dad by doing a water change on his 10 gallon neon tetra tank. dechlorinator? 7 year olds don't know about such things....... and i put the tetras in a drinking glass while i changed out ALL the tank water, dumped them back in and.... well, i don't think i have to tell you the ending.
 
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