While older concrete may have some trouble accepting the acid stain, there isn't an age limit. You may have more problem spots to be sanded or re-touched, but it's unlikely that your surface is too ...

If you have an old slab that has a lot of sand and ... of the stain and avoid an overlap mark. As soon as that acid stain hits the concrete, it's chemically reacting. So, if I roll across a ...

acid-stained or color-hardened concrete. Apply to concrete before hardening/densifying with Consolideck LS, then apply an appropriate Consolideck protective treatment to seal and enhance the color.