Ok.. As i thought.. the slabs must have been damp as they have attracted the geo-fix to lay on the surface after installation and hence has left a residue..
This can be removed with a residue remover.. the one posted above is a good one and Tile giant stores will sell that one.
After you have cleaned them then i would recommend a colour enhancing sealer which will give the colour like they are when they have been wet but not glossy look.
LTP colour enhancer from tile giant as well.. always follow the instructions carefully.
Important: - when using Grimex, Test the solution on an inconspicuous area before general application. Any alkalinity
remaining on surfaces treated with this product should be completely neutralised. This may be done with a
little clean water applied by sponge.
Hi forgot to ask 2 things: would you conisder the problem mild or severe by the pictures (need to gauge that for solution mix) and secondly is there another comparable product does not seem to be retail in Ireland? Failing that I can buy on- line anyway thank you again jm