Clarifying and chelating are not the same reset.
Clarifying shampoos rely mainly on surfactants to lift oil, silicone, dry-shampoo starch, and styling residue. Fine hair often needs this on a shorter cadence than thick hair—about every 1–2 weeks for many people—because limp roots show film quickly.
Chelating shampoos are for mineral film from hard water (calcium, magnesium, and similar deposits). Surfactant strength alone does not dissolve that film. Look for chelating agents such as EDTA, sodium gluconate, or phytic acid on the label when a normal clarify leaves fine hair flat.
If you are searching for the best chelating shampoo for fine hair, start with: (1) a chelating agent on the INCI list, (2) limited heavy silicones and quats near the top of the deck, and (3) conditioner on ends only afterward. This page does not name a single winner; compare current labels and your water/buildup type.