Whirlpool hot tub water often uses an alkaline or acidic adjuster to maintain the pH within the appropriate range to prevent corrosion and minimize equipment damage. Excessively high or low pH levels can significantly affect plants and lawn soil, disrupting the soil's acid-base balance.

Risks of using high-pressure water to rinse spa hot tub filters without removing them: 1. Damage to the filter structure 2. Incomplete cleaning 3. Damage to the filter's mounting and mounting mechanism 4. Potential water pressure issues

The pump, pipes, and seals in a spa hot tub may dry out after prolonged periods without water, accelerating aging. Some materials require a certain level of moisture to maintain elasticity and sealability. If these components are exposed to air for extended periods, they may crack or lose their function, shortening the lifespan of the spa hot tub.

Legionella is most active in warm water environments (typically between 20°C and 50°C), with optimal growth in the 35°C to 45°C range. Legionella growth is inhibited or stopped below 20°C or above 50°C. Therefore, whirlpool hot tubs, water towers, and other facilities with warm water temperatures are ideal habitats for Legionella.

In most cases, a 10 to 15 cm thick concrete slab is sufficient for a 4 to 6 person spa hot tub. If a larger load or poorer geological conditions are encountered, the thickness of the concrete slab should be increased appropriately and supplemented with measures such as steel mesh reinforcement.

HFL stands for "High Flow Limit." This code is automatically generated by the spa hot tub's control system when it detects a problem with water flow. Generally, an HFL error indicates insufficient flow or overheating in the spa hot tub's heating system.