Algae are plants like seaweed that tickles your feet when you’re paddling in the sea!

But did you know that many species of algae have many astonishing properties?

For example, spirulina is full of proteins. This brown alga has twice as much vitamin C as oranges!

The Japanese eat 7 kg a year, whereas elsewhere, people are only just starting to taste it.

It also turns out that algae are ideal for making beauty creams.

And because they can thicken and jellify, they’re used to make candy.

We now know how to make fuel and plastic from algae.

In France, a new company now uses algae to make smart phone cases!

But certain algae also cause problems. You may have heard of “green tides”.

Thousands of tons of algae get washed up regularly on the beaches of certain bays with shallow water.

Mechanical diggers are used to scoop them up quickly, because when they rot, they give off toxic gas.

This is not a natural phenomenon: these algae bloom because of certain agricultural fertilizers that end up in the sea.

Authorities have launched a plan to limit the use of these fertilizers and stop green tides spoiling beaches.