We currently live downtown and recently re-surfaced our courtyard/pool deck and have been fighting an ongoing battle with water staining from residual flow from our planters that looks like an oily iridescent sheen and then dries, leaving white chalky residue with yellow to orange rings. I noticed Wild Salsa's patio has the same staining issues. What the heck is it? I hadn't noticed staining before, but our new surface color is now a darker terra cotta.