Vinegar helps counteract the toxin for most jellies. I also have friends that swear by bentonite clay, which helps absorb the toxin and soothe the rash, but I haven’t personally tried it. It’s definitely a good idea to look up what critters are in your waters, both for how to keep yourself safe and for you to avoid disrupting their habitats.

And congrats! I also taught myself how to swim. I recommend joining an open water swimming group if any are around your area, you can learn so much just by watching how they swim.