Hello Christina and welcome back to planDisney!
If you plan to make a splash at a
Disney Resort Hotel, remember that “pool hopping” is not available. Resort pools are reserved exclusively for guests staying at that specific hotel, and many of them are gated, requiring a room keycard or MagicBand to dive in.
I did note that you inquired specifically about
Disney's Old Key West Resort. Once upon a time,
Disney Vacation Club members had the option of
Complimentary Alternative Pool Use (AKA "pool hopping"). However, pool hopping, even for DVC Members, is not allowed at this time. The good news is that Old Key West is home to
four great pools, including the Sandcastle Pool, which sports a 125-foot waterslide! You should be able to have a splash-tastic time right there at your resort.
See ya real soon!
Anne