EXPERTS are still waiting for the results of tests on a chemical which dyed a popular outdoor swimming pool.

Hinksey Pool, in Hinksey Park, South Oxford, has been closed since Saturday morning after vandals put a chemical into the water on Friday night.

It was strong enough to dye the entire 350,000-gallon pool a garish purple colour. Disinfectant and filtration has brought the 55m by 35m lido back to a more natural colour.

It is likely Oxford City Council will not get the results of a microbiological test until tomorrow and there are hopes it could reopen on Monday.

If the water is safe, it will be drained into the sewage system. It would then take another four days to be refilled, reheated and reopened. Oxford City Council is thought to be losing about £2,000 each day.

The colour has mystified local swimming pool experts.

Eddie Bjarnson, managing director of Aqua Services in Weston on the Green, said: "I have no idea what they could have done in a pool of that size.

"The only chemical I know would be something like iodine, which is a very strong purple - but how would you get hold of iodine unless you were a chemist?"

Barry Cavey, director of Yarnton-based Blue Water Pools, said: "It's very strange. There is nothing obvious that would cause the pool to go like that."

David Rundle, deputy leader of Oxford City Council, said up to 1,000 people would visit the pool on a hot day.

He said: "Quite a few people who have not been there do not realise the seriousness in terms of loss of a service and a loss of revenue to the council. I am hoping the culprits will be big enough to stand up and say they have done it."

Mr Rundle said the council would review security measures, as it was the second attack by vandals in less than a fortnight.

On July 28, yobs tried to damage the controls of the Splash facility next to the pool.

A Thames Valley Police spokesman said officers were continuing to investigate.