Corrected entry: Breathing the air from a glass with a pen is physically not possible that far under water. It is hard to breathe that way at 60cm bellow surface. Any lower and it becomes impossible - the fluid pressure on the lungs is just too high.
Corrected entry: When Cleveland hears splashing in the pool the first time, he opens the door and holds a flashlight in front to see. The shot is of the light out of the door, it is very obvious that it is raining, as it can be seen with the light. However, the next shot is of the outside and its obviously not raining. nor was it raining before any other shots.