I have been looking into it for a couple of months, but opted out to go to the Keys instead. Here is what a local sent me:
1. If you like wall diving, there is a 20-mile long wall running from the southwestern tip of PR to the south-central coast area, around an area called La Parguera. You can dive that area from the Copamarina Resort, using their in-house SeaVentures dive shop. The drive from San Juan is about 1hr45min and boat rides are 30-40 min. to the wall. There are also shallower reefs for the second dive of the day. You are guaranteed to see several green morays, beautiful black coral, turtles and, if you are lucky, eagle rays and nurse sharks. You can book directly via Dive COpamarina, or using Caradonna Dive Adventures as your operator.
2. If you are not into wall diving, but prefer nice reefs, then Culebra, a small island off the east coast of Puerto Rico, is the option. You can contact Culebra Divers (google search) for living accomodations- there are a cuple of new condo-resort complexes that offer very nice apartments for rent- look up Culebra Inns and Hotels. To get to Culebra, there are 2 options: 1. A short 15-minute plane ride from Isla Grande Airport in San Juan (this is a smaller airport close to Old San Juan) 2. A $10 ferry ride from the town of Fajardo off the east coast- the ferry leaves at specific times.
I actually was leaning more towards going to Culebra. If you want this local’s contact info, please e-mail me and I’ll send it to you. Good luck!