A common cause is mineral deposits in the water. If your area has hard water, it may contain high levels of minerals such as calcium and magnesium. When these minerals react with other chemicals in the water, they can form insoluble precipitates that float in your outdoor spa hot tub.

The typical water temperature in a spa hot tub ranges from 37°C to 40°C (98°F to 104°F). This range is comfortable for most people and can effectively promote muscle relaxation and relieve joint pain. However, when the water temperature exceeds this range, especially above 42°C (107.6°F), the body is more likely to experience discomfort.

The water in your whirlpool spa hot tub needs to be tested regularly, especially for chlorine and bromine levels. These disinfectants effectively kill bacteria and viruses in the water. It's recommended to test the water's pH, chlorine, or bromine levels at least weekly.

The filter is a critical component of the outdoor spa water system, capturing impurities and maintaining clean water quality. To prevent the formation of film, users should clean and replace the filter regularly. When cleaning the filter, it's best to use a specialized filter cleaner and high-pressure water rinse to ensure thorough removal of grease and impurities from the filter element.

While the tub's main material is sturdy, it's inherently heavy, and the added weight of a full tub of water makes moving it even more challenging. While some small, simple spa hot tubs may be relatively lightweight, most commercially available outdoor spa hot tubs are quite heavy, requiring specialized equipment and personnel.

Experts generally recommend that pregnant women should not soak in a spa hot tub for more than 15 to 20 minutes. This is because prolonged soaking in hot water can cause a woman's body temperature to rise, increasing the risk of heat stroke. A 15 to 20-minute soak allows for the relaxing effects of hydrotherapy without raising her body temperature to dangerous levels.