Many months ago, I put my nerite snail (Zippy, for her speed) in a half-gallon bowl for a few hours. She escaped, and crawled halfway across the table. She nearly died without water! We thought she was a goner. I put her back in the 10-gallon and hoped for the best.
She lived, but she was never the same. She stopped being her normal active self, disappearing for days behind the filter, barely moving from her hide-away. She stopped laying eggs. She seemed so depressed.
Then, on a whim, I bought a mystery snail. He's gold and very pretty. His name is Midas. You know, like the story... golden touch.
Suddenly, Zippy found new purpose in life. She was rather excited about this new friend, this fellow snail. She crawled all over him, tentacles out.
Both snails now traverse the tank every day. Zippy once again lives up to her name. She's even laying eggs again!
I never knew a snail could be so complex.