No Nitrox and really not needed for dives around Apo. The advantage of diving on Apo is more diving. It only takes 15 minutes at most from Liberty Lodge to any dive around the island so I made 4-5 dives each day and 60 minutes per dive. Plus being able to go to your room between dives to rinse off get batteries and eat. I was often the only diver on my dives in May.
Equipment
As far as what equipment to bring along will depend on how much diving you do. I usually get it 20-30 dives when I go to the Philippines and I'm more comfortable with my own equipment. My check-on bag usually is 40 lbs and 70 lbs are allowed check-in from the US. But within the Phillipines I get charged extra on domestic airlines over a lesser amount (only one bag allowed carry-on, can't remember the limit- 20lbs?? - my stuff - 500 pesos or so)and you are charged on fast ferries for anything you aren't carrying/keeping with you (can't remember the rate - maybe 30+pesos per kilo over allowed weight) plus porters lugging around your gear if you don't feel like it.
Apo Island
Libery lodge is quite (except for the 5 am roosters), electricity from 6pm - 9pm (still had enough time to charge my batteries but then I have multiples for camera and flash), so no fan at night, no air conditioning, water is from a cistern from which you use a pail to wash, bathe, flush toilet, etc. There is a descent variety of food to choose from like hamburger, pizza, eggs, rice of course and the fish catch of the day. So if you need a hot shower, tv, internet, party till 11-12pm and beyond, etc. this would not be the place to stay.
I've made two trips there and thought it was great. I don't mind mutiple dives at the same site even 3 days in a row especially now that I have a camera. There is always something new. Highly recommend the night dives in front of the lodge, I think I did 4 or 5 night dives with different guides - fantastic. First place I've seen Ribbon Eels.
