Hot tub maintenance – Everything you need to know: A simple guide

1. The Importance of Filtration

Effective filtration is crucial for maintaining clean and healthy hot tub water. Filters act as the primary line of defence against contaminants, trapping dirt, debris, and organic matter.

• How Filters Work: Water is pumped through the filter media, trapping solid contaminants while allowing clean water to pass through. The pleated structure of the filter increases surface area, enhancing its dirt-holding capacity.
• Filter Maintenance: Regular cleaning is essential for optimal filter performance. BISHTA recommends weekly rinsing with a garden hose and monthly deep cleaning using a specialist hot tub filter cleaning solution. “[A power jet washer must NEVER be used to clean filters as the power of the jet will damage the fibres of the weave in the fabric and render it useless as a filter.]” (1.pdf)
• Filter Replacement: Filters should be replaced annually, or every two years if two sets are used in rotation.

2. Water Chemistry: Maintaining Balance

Balanced water chemistry is vital for bather comfort and equipment longevity. Key parameters include pH, total alkalinity, and sanitizer levels.

• Daily Checks: Use test strips to monitor sanitizer and pH levels. Ideal ranges are: pH 7.0-7.6, bromine residual 2-4 mg/l, inorganic chlorine residual 2-4 mg/l, and organic chlorine residual 3-5 mg/l.
• pH Control: High pH can reduce sanitizer efficacy and cause scaling, while low pH can lead to corrosion. Use pH increaser or reducer as needed.
• Sanitizer Control: Sanitizers, such as chlorine or bromine, eliminate harmful microorganisms. Maintain appropriate levels and consider using built-in tablet dispensers for convenience. “[Never switch between Chlorine and bromine without consulting your retailer, as this can be potentially dangerous regarding chemical reactions.]” (3.pdf)
• Weekly Checks: Activate jets and waterfalls to assess for foaming and water clarity. Address issues with foam suppressant or clarifiers.
• Monthly Checks: Clean hot tub surfaces and replace filters with a clean set. Check and adjust pH and sanitizer levels.
• Quarterly Checks (Water Changes): Drain and refill the hot tub every 1-3 months depending on usage frequency. Use a system flush to clean pipework before draining. “Note: Up to 10% of UK drinking water contains legionella, which is safe to drink, but not something you want to be heated up in your hot tub!” (3.pdf)

3. Troubleshooting Common Issues

• Cloudy Water: Caused by suspended particles too small for the filter. Address by:
• Checking sanitizer levels and adjusting as needed.
• Shock dosing the water to oxidize contaminants.
• Ensuring filters are clean and functioning properly.
• Using a clarifier to bind small particles together for easier filtration.
• Foamy Water: Results from a build-up of products and TDS (Total Dissolved Solids). Minimize foam by:
• Showering before use to remove contaminants.
• Rinsing bathing suits with clean water after each use.
• Using high-quality chemicals and regular shock treatments.
• Opening the cover regularly for water aeration.
• Shock Treatment: Essential for breaking down contaminants and reactivating sanitizers.
• Perform weekly and after heavy use.
• Use non-chlorine shock for quicker re-entry.
• Address cloudy water post-shock by checking pH, alkalinity, water hardness, and bather load.

4. Preventative Measures

• Shower before use and avoid using lotions, cosmetics, etc.
• Rinse bathing suits with clean water only.
• Keep the cover on when the hot tub is not in use.
• Clean filters regularly and replace annually (or biannually with rotation).
• Maintain proper water chemistry and shock dose weekly.
• Consider annual professional servicing to ensure optimal performance and safety.

By following these guidelines and remaining vigilant about hot tub maintenance, owners can enjoy clean, clear, and healthy water for a relaxing and enjoyable spa experience.