Tests As Olympic Diving Pool Turns Green British sports star Tom Daley was among those who commented on the unusual colour of the diving pool in Rio.

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   Eyebrows were raised as the women's 10m synchronised platform final got under way in the green pool

The colour of the Olympic diving pool has changed from light blue to a murky green - but the cause is so far a mystery.

The unusual shade was obvious during the women's 10m synchronised platform final.
China won the gold, but all the talk was about the colour of the water at the Maria Lenk Aquatics Centre in Rio.
Britain's diving star Tom Daley tweeted: "Ermmm... what happened?!", alongside a picture of the pool, which contrasted sharply with the light blue colour of the pool beside it.

 
Water quality has been a major issue surrounding the Rio Games, but until now the concerns centred around the ocean and lagoons - not the pools.
Olympic organisers said water tests were carried out and there was no risk to athletes. The cause of the colour change is under investigation.
Canada team leader Mitch Geller suspected the cause was algae that multiplied quickly in the day's warm and sunny conditions.
"Everybody was scratching their heads going, 'What's going on?'" he said.
"I think that the filter is busted, but I'm not sure. It's not really dangerous.
"It's not like it's toxic or dirty or any of that. It seemed to get worse over the course of the competition."