Harry, some people use pine, some use hardwood (like oak).
You know, I was just talking with my wife, she is from Taiwan, and she says that The Phillipines is very close to her country, and that you have very similar plants, fauna, and geology. There is a professional bonsai artist from Taiwan, goes by the name Lo Minshuan who posts over at the IBC galleries often, bet he can tell you what he uses for soil components, and it may be things that are locally available to you as well.
here is the link if you have not been there before:
http://internetbonsaiclub.org/gallery
You should register, and look for Lo's latest post in the main gallery, and reply with your question about soils.
Good Luck
P.S. let me correct the spelling of his family name: Min Hsuan