I have a property that had a wet basement wall for years. The source of the water has been fixed, and I plan on applying UGL or similar water-proofing coating. But I'd like to clean the surface of the white scaley stuff. The fluffy white efflourescence wipes or hoses off, but some of the white stuff appears more stubborn (doesn't appear to be affected by wire brushing, etc). Don't want to use any kind of calcium dissolver, as I'm afraid it might damage the concrete block. Any ideas?
M.B.