load of info run... thanks.
unlimited dives - there's someone filling the tanks on the boat..? usually 3D3N how many the average dive we can get?
cost - for 3D3N usually how much it is..?
no need backroll - I love backroll... ahah biasa la newbie. (never have experience jumping from the boat b4)
comfort - I dont need luxury, because dont have money for it. bunkbed will do.
food - we are not cooking..? nice !!
18 divers - wow we will be like a school of big fishes in every dive site.
I need to try LOB one day...
3D3N trip will usually get you 7-12 dives, pending on your "semangat" and stamina. Some have done more, but that is already bordering on "kan cheong" already.

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Basically you average about 4 dives a day. Roughly, you start your 1st at 6-8am, 2nd at 11-12noon, 3rd (if you are not zzzzzzz-ing away) at 3-4pm and sunset/night dive at 6-7pm.
As long as you remember to monitor your dive profile (ie shallower depth than the previous) and getting the adequate surface interval time, it should be fine.
It has been a while since i went on a LOB trip, so am not too sure of the prices now - but it should retail at around RM800-1.2k
18 divers is normally the standard number of pax that the boat can comfortably accommodate. In such cases, the DM/group leaders on the trip will normally allocate or break the group into two or three, and dive at different profiles to avoid a "traffic jam" uw.