For South America - maybe consider:
Fernando de Noronha, Brazil
This archipelago of 21 volcanic islands and islets is a tranquil, off-the-beaten-path dive spot lying 200 miles off the coast of Brazil. Calm waters, a rich variety of marine life and a host of well-preserved shipwrecks, including the Brazilian Navy Ipiranga Corvette V17, make it one of the best places to scuba in South America – so it was an easy choice for our top spot.
Once underwater, divers enjoy crystal-clear waters with visibility of up to an impressive 45 metres, perfect for spotting dolphins, turtles, stingrays and coloured tropical fish.
The island chain makes up part of the mid-Atlantic ridge, an underwater mountain range stretching 15,000km through the Atlantic Ocean. Formerly 
a volcanic cone, its base lies 756 metres below the surface, so you’ll get to explore fascinating volcanic rock, caverns and coral formations.
As both Brazil’s first marine park and a Unesco World Heritage Site, more than 70 per cent of the island is protected. This includes tourist favourite Dolphins Bay, the world’s oldest, largest school of the mammals and a breeding ground for the acrobatic spinner dolphin (we kid you not). Nearby Projeto Tamar (tamar.org.br), a Brazilian environmental organisation, is worth checking out. Get involved, as the conservation centre is a good spot to witness cute, newly hatched hawksbill and green turtles take their first trip into the ocean.
And if you’re looking for a few more activities above the surface, you can go horse riding, dune buggying and surfing on the island chain, earning Fernando de Noronha the title “Hawaii of Brazil.”
What’s more, you, thankfully, won’t have to fight with hordes of other tourists for a relaxing dive trip – the secluded island promotes “sustainable tourism”, and only allows 420 visitors at a time. You’ll be able to enjoy its incredible marine life and natural wonders in peace.
The best time to visit is in the low season between April and November, when accommodation is cheaper.
Read more: Top five world's best scuba diving holidays - TNT Magazine
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