We were snorkeling 2 times per 1,30 hour during the day. I was impressed as it was my first time. People who had already been in Egypt weren't so happy like me :) there were only small yellow fish , feels like you're swimming in the fishing soup :) I didn't see bright corals or caves. But we were snorkeling only around Phi Phi islands. May be you'll find something around Phuket :) Snorkeling was included in the price of the excursion to Phi Phi. we didn't rent an ATV.