Carabassi beach is located just down Gran Alacant hill, although it belongs to Elche. The parking I usually go is the one on the old road to Santa Pola, which corresponds to boardwalk 0 but you can also use the other ones, closer to Arenales. Between 0 and 1 is where the nudist part is located so don't be surprised if you see naked people. Best time to go is all year round except July and August as it gets very crowded.
I made this video with my phone and with my camera therefore part of it is in landscape and part of it is in portrait. Will improve for the next ones.