This entry walkway had been improperly re-sealed around ten times. There was efflorescence that was leeching up through the slab which was damaging the sealers. The concrete was completely stripped of the previous sealers and then treated with Creto Deep Penetrating Sealer. This completely eliminated the efflorescence problem by waterproofing the substrate. A polyurethane topical sealer was then applied. Find out more at https://cretoseal.com/