Put the cover on the tub when it is not in use. Remember! In the case of
tubs filled with water but not in use over a longer period, remove the cover once a week for 30 minutes. It provides
adequate ventilation for the tub.

The spa cover has several purposes. Its use primarily reduces operating costs, since the hot tub water can be
warmed over a shorter period of time, and the energy consumption required for maintaining the water tempera-
ture is reduced as well. The use of the cover prevents leaves from falling into the tub, so there is less exposure to
environmental impacts. If the cover is fixed with clamps, it prevents children from using the tub without parental supervision.

Its use is also required for guarantee purposes. UV radiation may be harmful for the tub body without water in it.
Damage caused to the tub body by the sun is not covered by the guarantee.

Check the tub water!

Water sanitization

Disinfectants are distinguished on the basis of the active ingredient.

• Wellis Crystal with bio disinfectant
• With chlorine
• With bromine

1. Water hardness – recommended value: 8 – 12 nK

   This value is determined by the amount of dissolved calcium and magnesium salts and minerals. Hard water contains too much of these dissolved materials, which will result in scaling. It can cause significant damage to the tub wall, the piping and the filter, as well as the heating and mechanical units. Water hardness cannot be reduced by chemical treatment, and only scaling can be prevented. Soft water can be produced by the water softener with resin tank used for this purpose. Hot tubs should be used with 8-12 nK° soft water. (nK°=German hardness).

2. Setting the pH value – recommended value: 7.2 – 7

   The first important indicator is the water’s pH value. The pH value is measured on a scale of 0 to 14, where a value of 7 is considered neutral. Below that, water is acidic; above it, alkaline. The pH value of human eye is around 7.5. Over 7.8, water irritates bathers’ eyes. Experience shows that most of the problems are caused by a pH value that is too high. Inappropriate values reduce the effect of the disinfectant. The pH value of water is normally increased while the tub is not in use, and therefore, mostly pH reducers must be used.

   Recommended chemical: pH reduce

   pH reducer granules (100%) – package: 1000g It can be used together with any disinfectant; these pH reducer granules are highly effective.
   Dosage: in order to reduce the water pH value by 0.1, add 1kg of pH reducer granules to 100 m3tub water. It is recommended to add at the water inlet or at several points on the tub. Dissolve it in tap water before use (1kg pH reducer granules in 10 l water)

3. Wellis Crystal bio disinfectant

   This disinfectant kills or neutralizes microorganisms (bacteria, algae, fungi, viruses) present in water. Microorganisms are small microscopic forms of life that are not visible to the naked eye, and are constantly transferred into the water by rain, wind, or bathers. If they are not destroyed, they will be transferred by water from one person to another (causing illness or infection). Organic matter present in the hot tub water may turn the water opaque, or cloudy.

   Recommended chemicals: Wellis Crystal 100% bio disinfectant
   
   Pack size: 2×1 litre
   Chlorine-free disinfectant with a concentration optimized for hot tubs and small hot tubs. It can be used for all tubs equipped with a water circulation and filtering system. 100ml of Wellis Crystal is required for 1 m3 tub water. The presence of disinfectant in the water can be detected with the use of various testers. Aquacheck 5 in 1 tester.

4. Foaming

   Bubbles and colloidal contamination accumulate in different sizes of foam clots on the water surface. This foam is mostly formed by particles removed by water from human skin, cosmetics, body lotions, etc. and by the mixing of various chemicals. It jeopardizes the maintenance of aesthetic quality and cleanliness of your hot tub water.
   Foaming is a condition in which there are foam clots or a continual foam layer present on the water surface 30 seconds after the massage motors are stopped.

   Recommended chemical: Foam Stop 1000g – Anti-foam liquid for tubs
   
   Pack size: 1000g Effectively decreases foam formation caused by body lotions or other materials. Dosage: depending on foaming intensity, until foam disappears. After adding, wait until the material is thoroughly dissolved in the tub.

5. Filter cartridge cleaning

   Filter cartridges are designed to remove impurities from the tub water. Therefore, keeping them clean is essential. In case of highly contaminated filter cartridges, the system may not provide the proper amount of water flow. In this case, the control unit may disable operation if there is an error message displayed on the operating unit. The filter cartridge(s) must be cleaned weekly. It is recommended to soak the filter cartridges in the chemical solution Filter Cleaner for 24 hours.

   De-energize the tub before removing the filter cartridge(s). In case of operating without filter cartridge(s), there is a danger of damaging the circulation pump. Unscrew the filter cartridge(s) and use a strong jet of water to remove any deposited impurities from between the lamellas. Never use the tub without a filter cartridge. It is recommended to have an extra filter cartridge on hand

   The filter cartridges must be replaced every 3 months!
   The tubs currently have three different filter housing designs:

   • Skimmer housing
   • Floating filter housing
   • Wall-mounted filter housing

Filter replacement in a skimmer:

• Remove the filter cartridge by turning it counterclockwise
• While still in the water, tilt the filter cartridge a bit sideways to allow air to leave the cartridge
• Screw in the cleaned or new filter cartridge by turning it clockwise

• Exchange the water (except for tubs equipped with In-Clear)

• Find the drain in the tray and remove the closing cup.
• Screw in its place the metric spacer provided with the tub.
• Turn off the larger receiving part counterclockwise as far as you can.
• Then pull the receiving part towards yourself – the water will start to flow out of the tub.
• After all the water is drained from the tub, repeat the above described steps in reverse order.

Filling up the tub with water: please note that the tub must always be filled through the filter housing. If it is not, air can get into the circulation system. In this case, the tub heater may be damaged.
• Replace the filter cartridges with new ones.
• In case it is necessary, replace the UV bulb, or order a replacement.