Tropical atolls are coral reefs in the shape of a ring. Inside there is a lagoon of warm, calm waters.

The tropical atoll is the most popular coral reef, well-known for its characteristic ring shape, with a central lagoon of warm waters with depths of 30 to 80 m. This lagoon generally connects to the open sea through channels with the water is driven by the waves. The origin and formation of the atolls has been the object of studies and disputes among many scientists, but it is currently accepted that they are structures formed millions of years ago from other volcanic structures that have sunk, and the coral has formed on the top. Thanks to the combined action of the wind, waves and atmospheric erosion, the part of the atoll that stands out on the surface allows it to be covered with fertile land where plant seeds develop (coconut trees, bread trees, etc.) brought by the birds, the wind and even the sea currents, finally turning them into islands.

Clown triggerfish (Balistoides conspicillum)

Gray bamboo shark (Chilloscyllium griseum)

Other common marine organisms that can be found in this community

• Brownbanded bambooshark (Chiloscyllium punctatum)
• Whitespotted bambooshark (Chiloscyllium plagiosum)
• Humpback grouper (Chromileptes altivelis)
• White-banded triggerfish (Rhinecanthus aculeatus) 
• Palette surgeonfish (Paracanthurus hepatus)
• Bluespine unicornfish (Naso unicornis)
• Epaulette shark (Hemiscyllium ocellatum)