British diver Tom Daley has put the mystery surrounding the green water at the Maria Lenk Aquatics Centre back in the spotlight after revealing the venue was closed on Friday.
It has been one of the strangest stories of Rio 2016, with divers forced to compete in a pool that more closely resembled a pond.
The International Swimming Federation said a chemical imbalance caused the issue, which also affected the water polo arena.
But Daley expressed some concern when he found the Aquatics Centre shut, tweeting: "Diving pool is closed this morning. Hopefully that means we haven't been diving in anything too bad the last couple of days!"
Daley won bronze in the synchronised 10 metre platform.
Diving pool is closed this morning. Hopefully that means we haven't been diving in anything too bad the last couple of days!-- Tom Daley (@TomDaley1994) August 12, 2016