A $300,000 water filter system is being tried in the Torrens Lake in Adelaide in a bid to improve water clarity.

The trial will last until the middle of the year.

South Australia’s Environment Minister Gail Gago is hopeful the filtration will control outbreaks of blue-green algae, averting the need for any future closures of the lake.

“Every time that it reaches a level that is considered to be unsafe we close it down. This project though is about helping to ensure that we won’t need to do that again,” she said.

The lake has been closed since last week because an algal outbreak poses a public health risk.

Adelaide deputy mayor Sue Clearihan hopes the water filter system will help control the algae.

“The lake is obviously not looking good at the moment. Some people have described it as gelatinous in appearance,” she said.

“Obviously the blue-green algae makes the clarity of the water not good at all.”

The city council has been using a clay product in the lake in a bid to clear the water and have the lake open before February 29 - the opening night of the Adelaide Festival of Arts.

The clay helps kill algae by removing its food source.