They really aren't sealice, those are a parasite on fish, what he is referring to are jellyfish eggs and they do sting or fire, especially if they get trapped under you suit or somehing. There is a product called Sea Safe that repells them..just in case
Not sure if they are here yet or not, usually April-August are the months you need to be careful, but you never know. They post warnings on the beach in the hotel zone if there is a problem and then I guess you just have to get wet in the pool