If your sculpture if left out too long it will melt.
The rubber down tube will easily pull out and your pipe will be useless.
Not to worry, just wrap a small piece of paper towel around the bottom of the down tube and place it back in the ice.
Make sure it fits snuggly into the ice without hitting the bottom of the hole and put a few drops of water around the seal.
<To ensure your pipe lasts as long a possible be sure to wrap it in a plastic bag whenever it is in the freezer. This will slow the sublimation process>
Now place it back in the freezer and wait about an hour.
Please remember that water freezes. If you put your pipe in the the freezer when there is still water in it the pipe will clog and truly be useless.
When not in use place it back in the freezer.
Your pipe is guaranteed to last only the first use!
Following these guidelines will greatly increase the chance for multiple uses.