Prices range from around 800 to 1,000 baht for a half-day trip, generally including pick-up and drop-off at your resort, snacks and drinks and a couple of snorkelling stops.
We did a 1,000 baht trip with BB Divers and they took us to Ko Rad off the coast of Ko Kut (nearish to Sovena Kiri) and then to a spot out from An A Lay Resort. In between we had a beach break at Haad Taphao.
We asked before the trip started as to what we could expect and Manu from BB Divers did a good job of dampening our expectations -- "diving on Ko Kut is very relaxed", but even then the conditions were very disappointing. At both locations much of the coral was dead and there really wasn't much in the way of marine life. At Ko Rad they have sunk a number of artificial reefs, including an elephant and a horse -- fun for the kids at least.
This isn't to reflect badly on BB Divers -- they were professional and helpful throughout and the snorkelling gear was in excellent condition. They just don't have a lot of product to work with.
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