SteveM, you need to purchase some of the sealer that they applied over the concrete when it was dry, it is called Resina, they sell it at La Nieve in Elda, and I think most good large paint shops sell it. When you have it, simply jet wash the whole patio, and when the water has dried, simply apply the resina with a woolen style roller, you maybe better advised to wait till May time, as the weather will obviously be warmer and the Resina sticka a lot better, the application of the resina will bring back the colour of the patio and seal it from the weather.

Jerry, further advice please....
Went to my nearest big DIY place, Leroy Merlin at Gandia
asked for Resina para hormigon impreza and explained what it was for. I paid a small fortune for a large tin of
SISTA RUBSON SX9000 IMPERMEABILIZANTE EXTERIORES
Started early this morning....it went on like soapy water and now it´s drying it appears to have had as much effect as if I had washed it in soapy water... no effect whatsoever.
Have they sold me a wrong product?
If so, and I need to get Resina, is that just a generic name such as eg paint or is it an actual name of the product ?
Thanks