| I am going to go gingerly at it with a pin tomorrow. I did a searchand found the problem had been reported before and that pins are the best tool for the job. The problem is worst in hard water areas. I live in Bath which has very hard water so I especially bought the pre mixed formula but it is since putting that in that the problem started. Will let you know how I get on with it but any more suggestions or experiences would be welcome. | 
