Thanks for your reply Chris.
I have been using Unibond High performance sealant with superior mould resistance and a 35year guarantee.
The sealant still becomes mouldy after a few months.
About every three months, I need to renew the mouldy sealant around my bath and wash basin. I use quality sealant but still mould forms on the (fungus resistant?) sealant quite quickly.
Can someone please advise me as to the best sealant to use...