Name the problem first
Visible sediment, chlorine taste, staining and a health concern each call for different evidence and equipment.
Protect flow and serviceability
Ask about pressure loss, rated service flow, cartridge or media capacity, sanitation and replacement cost.
Health claims need evidence
Use certified-laboratory testing and appropriately certified equipment for health-related concerns. A sales demonstration is not a complete water analysis.
Questions
Make the next conversation clearer.
Do I need carbon with a softener?+
Not automatically. Add treatment only for a documented concern and understand how whole-home chlorine removal can affect plumbing hygiene.
Can a softener remove everything?+
No. A softener is designed primarily for hardness ions and should not be marketed as universal purification.