Lab data, decisions, and household-water playbook from a year of testing tap and well sources on the island. Written for our own kitchen — but anything in here should help if you live nearby.
Full breakdown of the two lab reports: ALS Bangkok (March 2026, Yoga House) and Suratthani Rajabhat (June 2025, tap A1–A4 + well B1–B4). What every sample means, what filter stack each represents, and where lead actually drops.
Lotus Hybrid (whole-house) and Lotus DY (under-sink). What each one removes, what it doesn't, and why "Lotus + DY" only protects the kitchen tap — not showers, laundry, or any other tap in the house.
Whole-house vs under-sink, RO vs ultrafiltration, the "0.007 vs 0.006 micron" sales claim, and how to remineralize RO water for kids without supplements. The full reasoning trail behind every recommendation.
Every place water touches the house — dishes, fruit and vegetables, laundry, dryer, shower, brushing teeth, cooking, ice, pets, plants — mapped against our lab numbers, with the cheapest fix per use. Heavy focus on dish-washing and washing produce, because those are the worst exposure routes.
The cost comparison (under-sink vs DIY whole-house vs 70k-THB installer kits vs Aquasana), the trap most buyers fall into, the exact stack that removes lead and other heavy metals for ~12,500 THB, plus what the recommended filter does NOT cover (arsenic, nitrate, fluoride, PFAS) and what to add for those.