Natural Chemistry | Scale Free

Natural Chemistry Scale Free is a calcium and mineral sequestrant for hot tubs and spas. It locks up the calcium and other scale-forming minerals in your water so they don't deposit on the heater element, the salt cell, the jet faces, or anywhere else heat and movement encourage scale to form.

Why scale is the silent spa killer: Calcium scale is the #1 cause of premature heater failure and dramatically shortened salt cell life. You can't see scale forming on the inside of a heater tube until it's already insulating the element and burning it out. On a salt cell, scale on the titanium plates short-circuits the chlorine generation. Scale Free stops the process before it starts by binding to calcium ions so they stay dissolved and harmlessly pass through the filter.

When to use it: Add Scale Free every time you fill or top up the spa, especially if you're on hard water (the entire Region of Waterloo, most of southwestern Ontario, and most well water). Also use it any time your calcium hardness reads above 250 ppm, after any pH or alkalinity adjustment that pushes those numbers high, and as a routine monthly maintenance dose for salt water spas.

How to use it: With the jets running, add 60 mL (about 4 tablespoons) per 1,500 litres directly to the spa water. For ongoing prevention in hard-water areas, add 30 mL per 1,500 litres every 4 weeks. Sequestrants break down over time as they bind their target ions — the monthly top-up is what keeps protection active.

Quick tips:

• If you have an Onzen or Spa Boy salt water system, Scale Free is one of the cheapest forms of equipment insurance you can buy
• Sequestrants and shock products don't always play well together — add Scale Free first and let it circulate for an hour before adding shock
• If you can already see white crusty deposits on the salt cell or heater, a sequestrant alone won't reverse it — you'll need a citric-acid descale