1 - You're also going to run into end of season issues as jh_MacLeod mentioned, as most of the East coast Malaysia diving ends in October. I think Redang and Perhentian will be closed by that point in November. Not sure if you'll find a shop to take you out. The reviews for Berjaya at Tioman are quite bad, especially considering the price per night, but otherwise the alternative accommodation is going to be very very basic, although much cheaper.
From wiki travel:
Due to the eastern monsoon, the season in the Perhentians (and all other east coast islands) is effectively limited to the period between the beginning of March or April until late October. Outside this period the seas can be very rough and choppy, skies overcast, and with currents that make swimming dangerous and most (though not all) accommodation options are closed. Do not believe the travel-agents when they claim the accommodations are open. Even if they will provide a room, restaurants and all shops (i.e. no place to get water, food, sunscreen etc.) are closed in off-season. If the restaurant is open, food choices will be very limited and over-priced.
It requires 2 flights from Singapore to get to Tawau in order to get the boat to the Sipidan area islands. You can check Air Asia to see if you can make it happen. Have to fly to Kota Kinabalu and then on to Tawau. If you some how can make it work, you'd better get in writing from your resort that you'll have a permit to dive Sipidan over several of the days you are there, otherwise you'll be at Mabul and Kapalai most likely. SeaVentures is the budget choice, but probably not a good one if you've snorklers with you. Better to stay on either of the islands.
2. Because of season you're probably limited to Sipidan area as far as Malaysia goes.
3. There is not really any day diving from Singapore. You can dive
Palau Hantu, but its usually only on Saturdays. Otherwise you might be able to dive around Bitan and Batam, but don't expect great things!
I'd probably suggest looking into spending that week in the Bali, Phuket, or Cebu area instead. Phuket is great for divers and snorklers alike and the flight schedules are much better than trying to get to Sipidan. Its prime Similan time and you could even do a couple days liveaboard. PM/contact Zippsy on this board for more information, especially about the White Manta which is based there from November onwards.
November is also prime Malapascua time which is reached via Cebu. I didn't snorkel while there, but the island is really nice and there might be snorkeling trips that can be arranged. Should be able to see Mantas and Threshers as well as some possible Hammerheads if they are around and you wanna go deep.
I am going to be based in Singapore between Sunday 6th November and Saturday 19th November. Flights and accommodation in Singapore are sorted and I'm planning on bringing as much kit as I can fit into my luggage. However, I would be very grateful for any comments on the following:
(1) Recommendations for a good dive outfit to take me plus 5 others (2 divers, the rest snorkellers) on a weekend Friday night (11th November) to Sunday night (20th November) Malaysian island trip (Singapore pickup with transfer to Mersing jetty in Malaysia) with Fri/Sat accomodation somewhere like Dayang, Tioman, Redang, Sipadan, Mabul or Kapalai?
(2) Which of the Malaysian islands like Dayang, Tioman, Redang, Sipadan, Mabul or Kapalai would you best recommend for (a) diving and (b) snorkelling?
(3) Suggestions of a good dive outfit (if different from the above) for a solo-diver and/or buddy pair who want to do some weekday day diving (shore or boat) from Singapore but without staying over anywhere?
Many thanks!
