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112. Onzen™ Frequently Asked Questions

1.12 Onzen™ Frequently Asked Questions


Onzen Questions


Question 1: How do I know if the Onzen system is working? Conduct a “Sanitizer Production test” (Also known as a Smoke test). This procedure activates the Onzen System while de-activating the filtration pump so you can see the mist of gas bubbles produced by the Onzen System. 

Question 2: What should I do if it fails the “Sanitizer Production test”? First, confirm you have the correct concentration of salt in the water “using sodium chloride test strips”. Then, start maintaining your water manually using “Boost” granular chlorine to sanitize and Adjust Up / Arctic Pure Salt Water Balance to balance pH. Continue to do this daily until the system is repaired by an authorized service technician. * Keep enjoying your hot tub!

Question 3: What should I do if the chlorine levels are too high? Turn the Onzen Output down (decrease “On” settings). Unless you added granular chlorine or shock to the water high chlorine levels mean the system is staying on too long for your circumstances. It may take a day or two for levels to normalize, or you can speed this process up by using a chlorine neutralizer, such as “X-it”.

Question 4: What should I do if the pH keeps increasing? Confirm that your Total Alkalinity is at the recommended level and reduce it manually with Arctic Pure Salt Water Balance. This is normal; all spa salt systems cause pH to increase.

Question 5: Will the salted water damage my lawn? This is very unlikely. The recommended concentration of salt is used is approximately 10% of the concentration of sea water. 

Question 6: Why is my water bright yellow, or bright green, or a rusty colour suddenly? This can happen if the pH gets too high. Lower the pH using Arctic Pure Salt Water Balance. High pH is a sign that the Onzen Output may be turned up too high, so you may need to adjust the Onzen Output After balancing the pH and adjusting the Onzen Output wait about 48 hours. If the colour of the water does not normalize you may need to replace the water. * Keep an eye on the pH and adjust it weekly to avoid this problem in the future.

Question 7: What is the typical amount of maintenance I need to do with Onzen?

  • Change the water twice a year.
  • Change the filter 4 times a year.
  • Check the Total Alkalinity weekly to make sure it is in the target range (Under 100).
  • Adjust the pH once a week. Salt systems naturally drive pH levels to increase, strive to achieve a Low pH level 7.2 must not exceed 7.6.
  • Check Calcium level monthly to ensure it is in the target range. Salt systems perform best with Low Calcium levels; strive for a target range between 50 – 150 ppm.
  • Adjust the Onzen Output “On” if hot tub use changes significantly.
  • Adjust the chlorine levels using “Boost” granular chlorine, after heavy use or if the Onzen Output is too low. Refer: Onzen Maintenance Schedule for further details.

Question 8: Should I use Best Defence or another scale remover? It is recommended that calcium be removed from the water in advance rather than adding a scale remover after the fact.

Question 9: What is the impact of phosphates on the Onzen system? High levels of phosphates (above 250 ppb) may reduce the effectiveness of sanitizer output. Question 13 What happens if my water becomes cloudy?

  • Test the water for chlorine content. If the level is low add Boost.
  • Check your filters as they may require replacement.
  • Check you pH level you may need to adjust you pH down.

Question 10 : Can I use softened water with my Onzen system? Yes. You probably have a water softener because your water is quite hard. Your water-softener removes calcium from your water and helps you achieve water with calcium content near the target range, between 50 – 150 ppm.

Question 11: Prior to draining spa water for refill purposes should any form of system flush be carried out? Yes you can, Arctic Pure ‘Fresh Start’. Use in accordance with the instructions on the container. Flushing the system components and hoses is helpful when you get biofilm and calcium build-up. It is good practice to do this at least once a year.