Where: 1,000 miles south east or a 2 hours and 30 minute flight from Miami, FL to the main island. Vieques and Culebra are 2 other small island 30 minute flight east of Puerto Rico proper.
What: The best spots for Scuba diving on Puerto Rico proper are La Parguera (south west corner), Aguadilla(north west corner) and Fajardo( north east corner). The south west corner La Parguera is dry and tens to have the best visibility because there is no run off from rain in the mountains.
When: Year round but You need to look at the direction of the wind and look to dive on the leeward side.
Times: Boats leave for a 2 tank dive around 8am.
What you need to bring: bathing suit, towel and certification card. Your dive gear but if you forgot anything rental gear is available.
Bonus: Snorkeling or Kayaking at night in one of the bio bays. The exploding bioluminescence varies in strength depending on the moonlight. You want to go when it is dark as possible. So a new moon or a cloudy night would work great.