It looked like a plague out of the Bible. It was enough to frighten beach-goers at several of the largest beaches around Sydney, Australia. But it turned out to be nothing more than a little algae.

The red waves hit Sydney beaches yesterday, as hot weather came with the transition from Spring to Summer. As you can tell from the photo above, not everyone was scared off by the red algae. But most beach-goers decided to stay away from the red-hued water..

Staying out of the red water was a good idea, according to officials; the algae is far from toxic, but can irritate the skin. The rare event closed beaches for most of the day, before they re-opened in the late afternoon.

We get algae that closes area beaches almost every year. But does anybody remember it turning water bright red ? Tell us your beach horror stories, here or on our Facebook page. And stay out of the water...