About Brian Hamilton & PoolToolbox

Why this site exists

Ask the internet how much chlorine to add to your pool and you'll get three kinds of unhelpful answer. The pool store tells you to hold 1–3 ppm, which quietly fails every stabilized pool in the country because the right target depends on your CYA. Generic calculator sites give you a number with no working, no side effects, and no idea whether your volume estimate is sane. And the genuinely good math is locked inside an app you have to install.

Meanwhile the actual chemistry is public and has been for years — molecular weights, saturation indices, the chlorine/CYA relationship. None of it is secret. It just needs implementing with some care, and explaining without an upsell attached.

Who's behind it

I'm Brian Hamilton, the creator and maintainer of PoolToolbox. The site is published by Hamilton Digital Media Limited and is part of my wider collection of calculators and tools at brianhamilton.xyz, alongside my puzzle projects.

My work here is building the calculation tools, checking their results, and explaining the assumptions behind them. I use published chemistry references and equipment specifications, with automated checks to catch mistakes when the code changes.

The sources below explain where the formulas and guidance come from. Each calculator shows its working so you can check how an input becomes a result, and the corrections address gives you a direct way to flag anything that needs another look.

The sources we build on

The chemistry here isn't ours and we don't claim it. The dosing relationships come from standard industry references — the formulas behind Taylor Technologies' watergram, the Langelier saturation index and its cyanurate correction, and the FC/CYA relationship developed and documented by the Trouble Free Pool community, which changed how stabilized pools are managed. Equipment guidance follows manufacturer specifications and published efficiency ratings.

Our contribution is the implementation, the testing, and the writing — plus a stubborn insistence on showing the arithmetic so you're never asked to take a dose on faith.

Corrections are welcome — genuinely

A site whose entire promise is "the numbers are right" has to mean it, which means being easy to correct. If you find a mistake — in a calculation, a formula, a recommendation, or a fact in an article — [email protected] goes straight to a person. We'll fix it quickly and note on the page what changed and when. No defensiveness, no quiet edits.

That's not politeness. Chemistry has edge cases, test kits drift, and products get reformulated. A correction channel that people actually use is the cheapest quality control there is.

How the site makes money

Some links to products earn a commission at no cost to you. That's the whole model — no ads that follow you around, no paid reviews, no sponsored placements, and nothing gated behind a signup. The rules we hold ourselves to are written down in the affiliate disclosure, and the important one is this: the math picks the recommendation, and we say so when the cheapest option is the right one. Plenty of the best answers in pool care — baking soda from the grocery aisle, liquid chlorine, a cover instead of a bigger heater — earn us almost nothing. We publish them anyway, because a site that recommends whatever pays best gets read once.

What's here, and what's coming

PoolToolbox is new. The water chemistry tools are complete — volume, chlorine, pH, alkalinity, stabilizer, calcium, salt, shock, water balance, dilution and more, all feeding the water test dashboard, which turns one set of readings into every dose at once. Equipment and cost calculators are being added now, with the guides that explain the why behind each number following close behind.

Your pool's details are remembered in your own browser so you don't retype them every visit — and they never reach us, which is the sort of thing that's easy to promise and easy to verify: it's covered in the privacy policy, and there's a button there that deletes the lot.