The water in the Olympic diving pool has left competitors baffled after it turned bright green.

The Rio pool, which hosts diving and waterpolo events, was perfectly blue during the men's 10 metre platform event the previous day.

The colour of the pool overshadowed the women's 10 metre platform final, with many making comments on social media.

British diver Tonia Couch said the pool's water was so green she couldn't see her partner Lois Toulson underwater, The Times reported.

The problem may come from a faulty filter or problematic water quality, the executive director of swimming's world governing body FINA told Reuters.

"No danger for divers, just not a good image for Olympic Broadcasting Services," said FINA's Cornel Marculescu, adding he was not sure how quickly the pool could be brought back to its normal hue.

In Tuesday's green pool, China's Chen Ruolin and Liu Huixia claimed gold, with Malaysia and Canada respectively taking the silver and bronze medals.Still, some divers shrugged off the colour change.

"Why does everyone ask about the water?" said Malaysian diver Pandelela Rinong.

"It's really normally for an outdoor pool so it's not a big deal for us."