As British diver Tom Daley pointed out Tuesday, something looks...different about the Olympic diving pool.
Ermmm...what happened?!
Compare the diving pool on the right with the water polo pool at left.
The aquatics center hosted the women's synchronized diving finals on Tuesday, and yep, that water was GREEN.
Here's the same pool two days apart.
The picture below on the left was taken on Tuesday morning. The one on the right was taken later in the afternoon.
One British diver even said the pool was so murky, she couldn't see her partner underwater.
#greenpool - @toniacouch says it was so green she couldn't see dive partner @LoisToulson under the water #Rio2016
People watching the divers had questions, and journalists in Rio couldn't immediately get answers.
.@TeamGB girls doing well in diving, battling for a medal in a very green pool! Did someone forget the chlorine tablets last night?
No-one will give an explanation for the green diving pool. An official statement from Rio2016 is being prepared!!!
BuzzFeed News has reached out to Rio officials for more information.
Someone is going to get out of this green pool and be bald. Or a mutant. #Olympics
The shade of green looked a little familiar.
Just waiting for Shrek to come out of the swamp that is the Rio diving pool! #Rio2016 #diving #GreenPool #BBCRio2016
"Jacques, no cleaning!" #GreenPool #Rio2016
According to one pool manual reviewed by BuzzFeed News, cloudy green water is usually the result of an algae problem.
A disinfectant or algicide can clear up the problem.
Another possibility for blue-green water is the presence of copper ions in the water. This can be the result of a bad pH balance in the water and requires the addition of a sequestering or chelating agent to remove the ions.
Make sure to shower, ladies!
By the way, China's Ruolin Chen and Huixia Liu won the gold medal.
UPDATE: On Wednesday, the color of the adjacent water polo pool also appeared to be changing.
This was how the two pools compared on Tuesday night.
And by Wednesday the color of the water polo pool appeared to become more murky.
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