Hot Tub Filter Core for Chemical Free Water Treatment


For Hot Tubs without skimmers. Works great for hot tubs without covers (Note: if filter core is used with Natural Spa your hot tub must be covered).

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For Hot Tubs without skimmers. Works great for hot tubs without covers.

Works with ozone and the Natural Spa treatment.

The Spa Core uses an all natural process, utilizing catalytic action & redox (reduction/oxidation) principal of dissimilar metals, made possibly by our unique reticulated sponge-like KDF media. Water twists & turns through the maze of copper-zinc fibers; the tortuous path ensures maximum contact with the media. Circulating water through the media on a daily basis causes a reaction that forms zinc and copper hydroxides. These controlled releases purify the water, creating a stable environment that prevents algae, scale & bacteria growth.

KDF media has been tested by the National Science Foundation and received NSF certification standards 42 and 61. Our reticulated KDF is currently used in commercial & residential applications, including the filtration of drinking water.

Recommended for hut tubs without a cover! Simply place the CuZn SpaCore inside your Sediment Filter and enjoy clean water with no effort. For Spas & Hot Tubs up to 500 gallons – typically lasts 3-5 months. Measure the inside diameter of your cartridge and choose the right size.

How To Use The Spa Core

  • Water flowing through the Spa Core is what makes it work. Your spa needs to circulate the water to provide maximum contact with the media. The best way to do this is to circulate the water 6 to 12 hours daily AND run the pump at low speed for at least 30 minutes after each spa use.
  • Don’t worry about pH with the Spa Core. They regulate themselves usually between 7.6 and 8 and occasionally from 7.4 to 8.2. Chemicals intended to control pH severely reduce the Core’s efficiency. Most pH parameters for pools and spas are based on using chlorine and are not relevant when the Core is used.
  • Likewise, the Cores tend to regulate water’s softness. The main reason water is hard is that calcium is present. The Spa Core does not remove calcium, but makes the water act softer by changing calcium’s cellular morphology so that it cannot adhere to a surface. The calcium does not deposit scale on surfaces.
  • If you test the water for softness in a Spa Core treated pool or spa, however, the test will show any calcium present because it does not distinguish between calcium’s various morphologies.
  • There are no health issues with the Core’s capacity to make water act softer. Using chemicals to soften the water, in addition to the Core, will restrict the efficiency and life of the Core. In normal operating conditions using the Spa Core no chemicals are needed for softening.

Additional information

Filter Core Size

6in x 2in, 6in x 1.5in, 6in x 1.25in


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