lukee0705,
I wouldn't panic too much, the saltiness of the water in that part of the Med / Aegean limits fish populations. The population up towards Bodrum is probably slightly better than Marmaris / Icmeler, but I wouldn't say it's vastly different. There's nothing big to worry about! Having dived in those water for a number of years, it actually gets quite boring seeing lots of rocks and odd wrasse, bream etc. It's the fireworms you have to watch out for. The fish won't do you any harm

I can't say I've ever been bitten by a fish and I'm in water on a weekly basis, daily in some months of the year! You'll soon be forgetting about the fish when the temperatures hit 40C and you're wanting a cooling dip. Just relax, have a lovely time (it's great diving off the top deck, you can make a much bigger splash in full scuba gear though!) and don't worry about Nemo and his friends.
Darren