Hi,
As you only have a week's vacation, already in the Philippines, but might be in the the tail end of the typhon season there, consider diving in the central Visayas specifically Cebu, which is away from the typhoon belt. My recommendation for you, will be to go to Malapascua, an island off the norther tip of Cebu but still part of Cebu province. It will offer you a chance to see Thresher and other sharks, mantas, an intact/big/historic wreck (Dona Marilyn), mating Mandarin fish, seahorses as small as your pinky nail and bigger, and tons of other small critters you probably didn't even know exist because you have not been to the Coral Triangle. Tip- stick to the Divemaster and tell him you like to see things of interest before you go underwater. Most divers in the Carribean cut off their 'umbelical cord' to the Divemaster and go fast underwater, missing most of the things worthwhile seeing. Just give him a decent tip at the end of your trip.
If you really want to go to a second destination in the Philippines, consider going to Moalboal, a town in the southwest part of Cebu Province. I think, though you are better off just staying in one place to dive and cut down on packing and unpacking, travel time, etc because of time limitation. Have the resort arrange your transfers, although tourists have been known to be more adventurous.
Cebu (Mactan Airport) and Manila are the only 2 places with real international airports and enough domestic flights to get you to/from Boracay. Tip- exchange your foreign money to the Philippine Peso at the airport. The money exchange is right after you get your bags and pass thru customs/immigration. Get lots of small change. You will get a 6% surcharge on credit card charges in the resorts (credit cards may not be accepted outside the big cities) and the exhchange rate for foreign money in the resorts are horrible (also in big city hotels).
Lembeh, Manadu, Sipadan also offer exceptional diving as they are in the Coral Triangle but when you start pricing these destinations, you will be pleasantly surprised that the PHILIPPINES IS THE BIGGEST BARGAIN IN THE PACIFIC.
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