Moon Jellys? No problem.
Stung by a Moon Jelly? Don't sweat it. Moon Jellies are the most common jellyfish inhabiting The Gulf of Mexico. Even though they have tentacles packed with nematocysts, their sting isn't really that bad. An easy way (and clean way) to denature the Jelly Sting is pouring vinegar on the infected area.
Make sure to remove any remaining stingers from your skin to eliminate further infection.
To relieve pain you can also soak the infected area in hot water and then apply a cold compress.
Apply vinegar and hot water as needed.