Cylinder head sealer?

[audi321]

Hi all. My Audi A4 is going through water every few weeks and having had the radiator and everything checked for leaks, someone has said it could be the cylinder head gasket? Then they said I could get some sealant which goes in the water to sort this out and it's about £25.

Has anyone any experience of this and does it work?

Cheers all.

[audi321]

OP here - I've put a bottle of K Seal in this week. Too early to tell if it's worked yet but I'll let you know in a couple of weeks. Cheers all for your advice!