Abnormally high water temperatures have turned one of Malta's most popular ponds green, according to a local mayor.

Images of the water feature at Santa Luċija's Garden of Serenity show it has turned murky green and foamy in recent days. 

It appears to be the result of algal blooming, which is caused by warm temperatures and nutrients, which can make water green.

The garden, known as the Chinese Garden, is one of the most frequently visited open spaces in the south of Malta, with its large, fish-filled pond as the central attraction.

But a Times of Malta visit to the location showed that the water in the pond turned green with patches of foam strewn all over the water body.

Photo: Jonathan Borg

Contacted for comment, Santa Luċija mayor Charmaine St John said the change in colour was likely due to the pond’s water becoming hotter than usual.

She said rain is expected on Friday, which will cool down the pond and restore it to normal.

Nevertheless, the Public Works department will ensure that all the garden’s pumps are functioning properly, St John said.

Environmental authorities will also inspect the pond, she said.

“We could have gone for shock therapy to clean the pond, but that might have killed all the fish,”  she said.

At present, the fish and other animals that call the area home are unharmed, she said.

A spokesperson for the Public Works Department said the department will assist the council as requested.

Photo: Jonathan Borg

St John said the Chinese Garden was recently refurbished and is regularly maintained.

The pumps feeding the pond were even replaced just over a year ago, she said.