Normal cleaners and fungicide dont touch it. IT's not on teh tiles or grouting but on the sealant between the wall/tiles and bath. Not all the way round either just near the shower bit.
DO I have to remove teh whole of teh sealant that goes round the bath or is there some miracle cure. Our plumber refused to do it as he said it was too fiddly to have to remove all the sealant and put down more