1. by Isaac David Benhaimoud
CORAL REEFS
by Isaac David Benhaimoud

2. THE CORAL REEFS
A living coral reef is an underwater ridge or mound built of fragments of coral sands and limestone.
This is the largest coral reef.
It it is visible from the space.
The Great Barrier-Australia

3. 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. .

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

5. THE MESO-AMERICAN REEF
It is the second largest coral reef in the world.

6. 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.