I have a 4" clown loach that has developed a strange habit. He'll dig up all the trumpet snails in the sand, and place them in a pile in the back corner of the tank. He doesn't eat them, or even try to, he just likes to round them up. As soon as he takes a break they'll crawl away, and then he has to start all over again. Maybe I need to provide better in-tank entertainment for my loaches...

