How Do I Maintain The Ozone System In My Hot Tub?

Hot tubs equipped with the ozone sanitation system are easy to use and maintain. Follow the steps below to make sure your system is operating and providing the best quality water.

Fresh Water (FW) products are the water care products which Mainely Tubs recommends for complete synchronization and sanitation.


Chemical Start-Up:

  1. Balance total alkalinity/pH
  2. Balance calcium hardness
  3. Add ½ to 1 ounce of Freshwater Chlorinating Granules
  4. Wait 1 day
  5. Check and adjust pH level as needed


Prior to Each Use:  Add ½ to 1 ounce of Freshwater MPS Non-Chlorine Oxidizer (depending on gallon size of hot tub)


Once a Week:

  1. Wipe down the water line with a non-abrasive scrub pad
  2. Check total alkalinity and pH using a Freshwater 5-Way Test Strip. Depending on results, you may need to adjust the water with Freshwater pH/Alkalinity Up or Freshwater pH/Alkalinity Down, following directions on the bottle.
  3. Super oxidize the spa by adding ½ to 1 ounce of Freshwater Chlorinating Granules (with the Everfresh water system, it is only necessary to get your chlorine level between 3-5 ppm once per week [more often depending on usage of spa]). It will usually register at 0 ppm. 
  4. On a different day than you do the preceding steps (we suggest the next day), add 2 ounces of Freshwater Stain and Scale
  5. Rotate the filters

Freshwater Chlorine is used only as a shock. The Ozone System provides the sanitation for your spa, provided you are following the above directions.


Once a Month:

Remove filter(s) and clean using Freshwater Instant Filter Cleaner, following the directions on the bottle. Be sure to thoroughly rinse filters to remove all trace of cleaner. Please make sure you clean your filter(s) at least once a month

An extra set of filters will make this process easier


Every 4-6 Months (depending on water quality):

  1. Terminate power to the spa
  2. Completely drain the spa according to the instructions found in your owner’s manual
  3. If needed, clean interior of the spa using Freshwater SpaShine Hot Tub Shell Cleaner and a non-abrasive scrub pad
  4. Clean the cover surface with Freshwater Cover Shield
  5. Refill the spa using a garden hose placed directly into the gray-capped filter standpipe
  6. REPLACE the Continuous Ion Sanitizer Cartridge with a new unit
  7. Make certain the spa is circulating before allowing the heater to operate




  1. Never use your spa if the water is cloudy.
  2. You may need to add Freshwater Chlorinating Granules more often if hot tub use is more frequent than usual and/or more bathers
  3. To suppress foaming while in the tub, use Freshwater Defoamer
  4. For oily films, soap, or heavy bather loads (cloudy water), use Bright & Clear
  5. To remove excess build up in the plumbing lines, use Jet Clean prior to draining, follow directions on the bottle
  6. For an extra deep clean, you can use Freshwater Hot Tub Filter Cleaner to soak the filters overnight

All recommendations are based on 1-2 people; 2 times per week for a 20-minute soak