As a native of sunny Florida, I can tell you that the key to non-yucky hair is to wash it right after swimming in a chlorinated pool, preferably with a chlorine-removing shampoo if you can find one, and using some kind of conditioner for extra dry hair (the kind you leave on for 1-3 minutes, at least). A lot of pools around here have little stand up showers with really really cold water, where you can at least rinse out the chlorine, if not repair the damage right away. If you're in the sea, then washing it soon after swimming with regular shampoo and conditioner will work just fine. Also, some hot oil treatments or hair masks would not be out of line, maybe once a week.