This is almost certainly a very bad thing to do to a fish

This is almost certainly a very bad thing to do to a fish:

Goldfish + Mountain Dew + 9 Volt Battery = Lives - Google Video

A goldfish gets its bowl drained of its water, then the water gets replaced by Mountain Dew and the goldfish dies. The Mountain Dew is then drained and replaced with water. The goldfish is still dead, but is ressurected with a 9 volt battery.