MacGyver was a Mollusk

From the L.A. Times:

The guest of honor in the aquarium's Kids' Corner octopus tank had swum to the top of the enclosure and disassembled the recycling system's valve, flooding the place with some 200 gallons of seawater.

"It had grabbed the tube that pulls out the water and caused it to spray outside the tank," said aquarium education specialist Nick Fash. Judging by the size of the flood, Fash estimated that the water flowed for about 10 hours before the first staff member, Aaron Kind, showed up for work.
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The tiny octopus, which is about the size of a human forearm when its appendages are extended, floated lazily in the water that remained in its tank.

It watched intently through glass walls and portholes as workers struggled to dry the place out in time for the day's first busload of schoolchildren to arrive on a 9:30 a.m. field trip.
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The incident was reminiscent of a 1994 incident at San Pedro's Cabrillo Marine Aquarium in which an octopus named Octavia pulled a plastic pipe loose.

That giant Pacific octopus died when all of the water in her tank drained out.

Since octopuses are considered by many to be the most intelligent invertebrate -- and to have good memories -- Fash said he jury-rigged his octopus tank piping with clamps and tape in hopes of thwarting any further mischief by its occupant. "She would need tools," he said of his octopus, which until now had no name.

"Some people are suggesting we call her 'Flo,' " he said.