Everything you need to know about balancing your water for the first time, and maintaining your hot tub ongoing.
Startup, Maintenance & Water Care
To ensure your hot tub is safe and healthy for use, please test the water chemistry regularly and adjust it following the instructions included in your Moji startup chemical kit.
Hot Tub Chemical Treatment
Regular water maintenance is an excellent habit to form from the first use of your hot tub. Keeping on top of your water maintenance and correct use of your filtration and cleaning settings has the potential to significantly reduce the amount of sanitiser you need to add to your tub. To ensure a well-balanced and correctly sanitised hot tub it is vital that you have a test kit capable of undertaking the following water tests:
- Free Available Chlorine or Total Bromine
- pH
- Total Alkalinity
These tests give the hot tub operator the information needed to maintain a well-balanced and clean tub. A sanitiser removes harmful bacteria and is essential for clean and safe water. Users may choose between a rapid acting sanitiser (Spa Master Super Chlor) or slow-release option (Spa Master Bromine). Water hardness levels are also important, but not tested for with standard test kits, it may be necessary to increase soft water hardness levels using Spa Master Water Hardener. Calcium hardness relates to the levels of minerals in the water. If the level is too low, the water will eat away at anything possible to get the needed minerals. If the mineral level is too high, scaling or calcium deposits will form.
Recommended Water Quality Criteria
| Criteria or Test | Recommended Result | Most Desirable Level |
|---|---|---|
| pH | 7.2 – 7.6 | 7.5 |
| Free Chlorine | 2 ppm – 4 ppm | 3.5 ppm – 4ppm |
| Total Bromine | 2 ppm – 4 ppm | 3 ppm |
| Total Alkalinity | 80 ppm – 150 ppm | 120 ppm |
| Calcium Hardness | 80 ppm – 150 ppm | 120 ppm |
Notes:
- ppm = parts per million, as shown on your test kit
- Avoid testing immediately after a chlorine shock dose as high chlorine levels can alter test kit accuracy
Water Testing
pH and Free Chlorine / Total Bromine levels should be tested prior to use and adjusted accordingly. Testing can be carried out using either simple dip test strips or a tablet/dropper type test kit. The main jet pump/s should be running while dosing chemical to ensure rapid mixing and to avoid chemical remaining on the hot tub surfaces — let the pump/s run for one full turnover (around 10 minutes) in between chemical adjustments and before using the hot tub.
Shock Dosing Treatment
Where a hot tub is under continuous heavy loading, a minimum free available chlorine or total bromine level of 3ppm should be maintained at all times. Shock treatment should also be carried out at least weekly to break down organic contaminants and unwanted chlorine products. A shock treatment is a single large dose of either Spa Master Super Chlor or Spa Master Oxygen Shock (20g per 1,000L of water). Due to the higher than normal levels of sanitisers after shock treatment, use of the hot tub should be avoided for 12-24h following treatment for comfortable use. Your tub likely is due for a shock treatment if you experience any of the following:
- Loss of clarity
- No chlorine reading for extended periods
- After heavy loading
- Presence of chlorine aroma (indicates high chloramines)
- Change of water colour
Additional Treatments
- Spa Master Defoamer can be used to remove excess foam or bubbles, commonly caused by moisturisers and excess shampoo
- Spa Master Spa and Pool Clarifier removes fine particles to produce clear sparkling water
- Spa Master Spa Kleen added prior to a water change helps clean pipes, jets and pumps
Hot Tub Loading (the number of uses per day)
Hot tubs can have heavy loading due to the comparatively small water volume and large number of bathers per day. If the hot tub water is not treated correctly, considerable numbers of disease producing and other microorganisms will accumulate, particularly in the surface layer of the water. Loading factor is also compounded by:
- The close proximity of bathers in the hot tub which could allow the transfer of germs from a carrier to another person sitting next to the carrier. Consequently, there is only a short period of time in which to sanitise the water.
- The warm temperature of tub water promotes bacterial growth.
- The fast transportation of germs throughout the tub because of rapid water movement.
It is therefore evident that the proper chemical treatment and efficient filtration must work together. The filter should operate for a minimum of three hours each day.
Change of Water
Water should be changed a minimum of every six to twelve weeks in private hot tubs. Every six weeks is recommended for heavy loads, twelve for lighter use. The filter cartridge should be cleaned every 4 weeks with Spa Master Cartridge Cleaner. Changing the water is the only way to remove finely dissolved solids. Hot tub water should be changed if the following cannot be resolved with shock dosing:
- Loss of clarity
- Presence of aromas
- Change of water colour
Recommended Startup Treatment Procedure
- Fill hot tub to slightly above the recommended line or where the skimmer operates most effectively.
- Turn the main jet pump/s on for dosing chemical – let the pump/s run for one full turnover (around 10 minutes) in between chemical adjustments.
- Test for total alkalinity and adjust with Spa Master Alkalinity Up (125g will raise total alkalinity approximately 80 parts per 1000L of hot tub water).
- When total alkalinity has been adjusted to 120 ppm, test and adjust pH to 7.5.
- Use Spa Master pH Decrease to lower (30g per 1000L will decrease reading by 0.6 parts) or Spa Master pH Increase to raise (30g per 1000L will increase reading by 0.6 parts).
- Depending on test reading, at start up, add Spa Master Water Hardener (100g will raise water hardness approximately 80 parts per 1000L of hot tub water).
- Add an initial dose of your chosen sanitiser – either 20g of Spa Master Super Chlor per 1,000L of water OR load your adjustable bromine dispenser with 2 tablets of Spa Master Bromine per 1,000L of water. A floating dispenser must be used for bromine tablets – when placed into the filter basket there is a high risk of damage to your pumps and filtration system over time.
- After the startup chemical treatments, the level of free chlorine should be allowed to come down to below 5 ppm before use for comfortable use.
Depending on the size of the hot tub, filtration cycles will vary. Most tubs will require a minimum of 3 hours of filtration a day. Every hot tub varies for one to another regarding chemical demand. You will become accustomed to your own tub and know what quantities of chemicals are required to make necessary adjustments.
Filter Cleaning & Maintenance
Your Moji hot tub is equipped with a single filter that needs regular maintenance. Users with low usage may find they only need to clean their filter once a month, whereas a tub with high usage could require cleaning every 1 to 2 weeks.
What is the purpose of a cartridge filter?
- The cartridge filter in a hot tub is specifically designed to remove particles from the water: soaps, chemicals, perspiration, body fats, oils, and fine particles of dust or dirt.
- Once taken from the water, these particles are stored within the polyester fiber pleats. To prevent cartridge failure, these pleats will have to be cleaned regularly. Below is a step-by-step guide to cleaning the cartridge.
What is the purpose of a cartridge filter?
- Firstly, cycle the pump “A” button to “off” to turn the pump off. This will prevent any debris from being drawn into the circulation system while your filter is removed.
- Place your hands under the front panel of the filter box and slide it up to remove it, then place it somewhere safe.
- Slide the tray out from the filter box and wash any large debris off the tray.
- Reach into the top of the filter and locate the small handle on top. Turn it anti-clockwise to unscrew it and remove it.
- Wash the filter using a garden hose, working from the top down. Open the pleats with your fingers so the water can reach the bottom of the pleats where most of the debris accumulates. You may want to invest in a hot tub filter cleaner wand that attaches to a hose to make this task easier and quicker. Moji recommends the Life Products Water Wand Pro.
- Soak the cartridge for 24 hours in the cartridge cleaning solution provided in your start-up kit. Using a bucket will minimise the amount of solution needed. We recommend turning the filter halfway to ensure both ends are fully submerged in the solution.
- Rinse the cartridge thoroughly after removing it from the bucket until the water is free of foam.
- The cartridge is now ready for use again.
- Place the filter in the filter box and turn it clockwise until it’s just snug. Be careful not to over-tighten it.
- Replace the skimmer tray between the two slots in the filter box and push it all the way back.
- Slide the front panel back down onto the front. The flap should swing freely through the opening.
- Press the “A” button on the pump until “auto” is displayed on the screen.
Moji Tip! It’s good practice to have two filters so when one is being cleaned, you have one to put back in your tub. Doing this also means you can soak the filter in the cleaning solution for a longer time. We recommend and supply Magnum Filters for all our Moji tubs.
Replacing the Filter Cartridge
- Your filter cartridges contain a filter fabric specially designed for filtering hot tubs. However over time the cartridge will block up to the extent that it will have to be replaced. Unlike many other types of Cartridge filters i.e.: carbon block, Polyester pleated Cartridge filters do not have a predefined hygienic life. It will gradually plug up over time due to the soaps, chemicals, body fats, and very fine particles. It is important that the cartridge is replaced when this occurs. Failure to do so could result in inadequate filtration and ultimately equipment failure.
How can I maximise the life of my filter cartridge?
- Maintain hot tub water chemistry in proper balance.
- Clean the cartridge in accordance with its cleaning instructions.
- Do not scrub the filter with a stiff/coarse brush.
- Do not use a pressure washer on your filter.
- Rotating two cartridges will prolong the filter’s life considerably.
