3 - staying in the same area, even around the same coral or outcrop
can lead to fish getting used to you and becoming bolder
it might take quarter of an hour to get your shot but that's the fun of it
4 - many fish are disturbed by diving directly down upon them
with many it seems to be better to dive several metres away and...
to approach them swimming horizontally on their level
5 - with shy fish, a 'burst' of shots may pay - you may only get one chance