by Isaac David Benhaimoud

THE CORAL REEFSA living coral reef is an underwater ridge or mound built of fragments of coral sands and limestone.

The Great Barrier-Australia

This is the largest coral reef.

It it is visible from the space.

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• Corals grow in clean water with temperatures between 20 and 30 Cº.

• They also need light.

• A special type of algae live in association with corals: the zooxanthellae, which produce the different colours.

RICH UNDERWATER LIFEA lot of species living in the coral reefs; 400 species of corals,1800 different species of fish,125 of sharks and 5000 of molluscs.

THE MESO-AMERICAN REEF

It is the second largest coral reef in the world.

CORAL BLEACHING• Coral bleaching is the whitening of corals due to the

increase of temperature over prolonged periods of time and pollution.

• Corals expel algae living with and lose all their colour and their ability of building more reefs.