An experienced snorkel guide should know that those water conditions were not for tourist snorkelers who should be considered to only have limited snorkeling experience under ideal conditions. Tow rings should be allotted to those by offering, and to take that many people into the channel in those conditions was in my opinion injudicious and dangerous. The fact that all of the snorkelers suffered physical (and emotional) injury from being banged up on the reef, not to mention two drowning from the the water conditions, indicates that a different location would have been a proper alternate choice...for tourists who should be assumed unfamiliar with the activity in that location under those conditions. It is terribly sad for all involved, families, etc. and the tour operators.