Got a basement with some old brick walls that require a tanking base coat of s&c with SBR. I suspect the bricks to contain a hi level of hygroscopic salts due to the other side of the wall leading to earth and plus a general hi level of moisture in the basement. Was wondering whether to add a salt retarder in with the mix to the base coat or apply a seperate coat maybe a slurry coat with s&c and salt retarder before the tanking coat?? also wondered if anyone can recommend a good salt retarder...