My adult corys don't run away when I'm around but they don't move at all, just sit around all day, and then when I turn the tank lights off they both start searching through the gravel all around the tank, (regardless of whether I'm sitting right there or not). My baby corys in my other tank are constantly swimming all over the tank day and night, up to the top and all around the bottom. They never hide and are always moving- very busy.