I'll take a punt on the fish, Purple Tuskfish.
The other critter .... seem something like it before but can't remenber
Looks like when your crabs get crabs...
It looks like a venus tusky. top fin is different to the grass tusky (purple).
Finally got one
The worm could be some kind of Bristle Worm, well that's my guess.
Dids if no one can ID it, I can send the phot down to the boffins at the lab.
Yes I believe you've got it Blacky, the prize is yours.
http://www.mesa.edu.au/marine_worms/marine_worms02a.asp
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Your not related are you
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