Why did diving pool change from blue to green in Rio Olympic Games?

In the diving competition of Rio Olympic Games, a strange phenomenon happened, which once reached the climax of public opinion. The thing is, in the women's diving competition, the original crystal clear water slowly turned dark green at the speed visible to the naked eye, which surprised everyone present and formed a sharp contrast with the water next to it. Why is this happening?

Many netizens began to imagine that athletes urinated while diving. Or did the organizer deliberately turn the pool green to make the game more enjoyable? When the IOC staff said this, these doubts were broken. The staff of the Olympic Committee hastily gave the answer that the green of the pool water was caused by the reproduction of algae plants in the pool water. However, many people do not agree with this answer. Everyone knows that this is the venue for such a large-scale competition as the Olympic Games, and it must have been heavily screened. If there is algae in the swimming pool, it will be detected, and such a thing is not allowed to happen. At the same time, there will be staff to clean and disinfect this swimming pool, so everyone does not agree with this statement given by the staff of the Olympic Committee. So what causes the pool water to turn green? ?

According to the investigation of water quality experts, the liquid usually used for disinfection of swimming pools is chlorine-containing disinfectant. Later, the chlorine-containing disinfectant was used up, and the staff disinfected the swimming pool with hydrogen peroxide. As a result, two chemicals appeared in the swimming pool. When chlorine is accidentally hit, it will react with hydrogen peroxide. Disinfection didn't work, but caused the swimming pool to turn green due to the imbalance of pH, so there was a strange phenomenon that the swimming pool turned green slowly. To confirm this statement, experts tried to add two substances to the same glass of water. It can be seen that in a few minutes, the clear water slowly turned green, which solved everyone's strangeness, so chemistry is closely related to our lives.