# LSEye

> Professional water chemistry calculator for pool and spa service technicians. Computes the Langelier Saturation Index (LSI), generates complete, ordered chemical treatment plans with exact doses, reads LaMotte SpinTouch test results from a photo (OCR), and explains its reasoning. React + Vite PWA.

LSEye is built for working pool pros, not homeowners. It accounts for pool vs. spa, surface type, salt systems, bromine, indoor/outdoor, and chemical cross-effects, and it simulates the treatment sequence to avoid precipitation and unsafe combinations.

## Core pages
- [Calculator](https://lseye.com/tool): Main tool — enter readings (or snap a SpinTouch photo), get LSI and a full dosing plan.
- [How the Calculator Thinks](https://lseye.com/logic): Plain-English breakdown of the dosing engine — targets, LSI solving, chemical interactions, wait/separation logic.
- [Chemical Guide](https://lseye.com/chemicals): Reference for common pool/spa chemicals, uses, and handling.
- [Learn](https://lseye.com/learn): Educational content on LSI and water balance.
- [Gear](https://lseye.com/shop): Equipment reference.

## Notes
- The dosing engine is a standalone, versioned package (puddle-dosing-engine) shared with the company's field-service app, so the public calculator and the techs' tools give identical recommendations.
- Acid + chlorine is the only chemical separation requiring an on-site wait (toxic gas); other separations are handled spatially (pools) or by pre-dissolving and staggering across the visit (spas).