They were 30 feet underwater in Key Largo, using dive knives and carving tools to transform the pumpkins.
The biggest challenge was keeping the pumpkins from floating to the top of the water.
They were also joined by some fishy spectators while carving.
The winners, two women from Detroit, won a free dive trip for their perfect pumpkin.
----------
* Follow us on YouTube
* More local news
* Send us a news tip
* Download the abc7NY app for breaking news alerts