Agree with Ali Baba ... it's on beach looking over a nice coral reef and nice views and nice quiet beach (Heavenly Bay).
Agree with Castara Retreats but it is not on the beach ... it is up the hill with marvellous views of the beach ... very nice place though.
Agree with Beach House too ... that is on the beach in Heavenly Bay, Castara.
But also ... think about the Blue Marlin Suite at Naturalist, Castara ... it's almost IN the sea

... it is a bit exposed to the elements but it is as close to getting wet as you can be.
Many options ...
Regards