100 Hot Tub Terms You Need to Know As A Hot Tub Owner

Hot tub ownership is a source of relaxation, rejuvenation, and endless enjoyment, but it also comes with its own unique language. Whether you’re a seasoned hot tub enthusiast or a first-time owner, understanding the terminology is essential for making the most of your hot tub experience.

In this comprehensive guide, we’ve compiled a list of 100 crucial hot tub terms and their definitions to demystify the world of spas. From water chemistry and sanitation to equipment and maintenance, this resource will empower you with the knowledge you need to keep your hot tub in pristine condition and fully enjoy its therapeutic benefits.

So, let’s dive in and explore the fascinating universe of hot tubs, one term at a time.


The Ultimate Hot Tub Glossary

  1. Acrylic: A durable and easy-to-maintain material commonly used for spa shells, known for its resistance to staining and versatility in shape and color.
  2. Aerator: A device that injects air into the water to create bubbles and enhance hydrotherapy. Also called an air blower.*
  3. Alkalinity: The measure of the water’s ability to resist changes in pH, which helps stabilize pH levels in a hot tub. High alkalinity will make it hard to change the pH. Low alkalinity will cause pH levels to become sporadic and hard to control or maintain. The recommended Total Alkalinity level for spas is between 80-120 ppm.
  4. Alkalinity Increaser: A chemical used to raise the alkalinity of spa water.**
  5. Alkalinity Reducer: A chemical used to lower the alkalinity of spa water.**
  6. ASTM (American Society for Testing and Materials): A widely recognized standard for evaluating the quality and safety of hot tub covers.
  7. Balboa: A reputable brand known for manufacturing spa control systems and components, valued for their reliability and performance.
  8. Biofilm: A slimy layer of microorganisms that can form in the plumbing of a spa.
  9. Blower Check Valve: A one-way valve that prevents water from entering the air blower.
  10. Bromine: An alternative sanitizer to chlorine, often used in spas for its effectiveness at higher temperatures.**
  11. Cabinet: The exterior shell or enclosure of the spa. Interchangeable with Skirt.
  12. Calcium Hardness: The concentration of calcium ions in the water, can impact water balance and equipment.
  13. Calcium Scale: Deposits of calcium and other minerals that can build up on hot tub surfaces.
  14. Cartridge Filter: A type of filter that uses replaceable filter cartridges to trap debris. A popular brand is FROG @ease In-Line System.
  15. CEC Testing: Compliance with the California Energy Commission’s energy efficiency standards for spas.
  16. Chlorine: A chemical sanitizer used to disinfect hot tub water by killing bacteria, algae, and other contaminants.
  17. Circulation Cycle: The continuous operation of the circulation pump for water quality. Interchangeable with Filtration Cycle.
  18. Circulation Pump: A low-speed pump that circulates water continuously for filtration and heating.
  19. Clarifier: A chemical additive that helps improve water clarity by aggregating small particles.
  20. Cover Corner Radius: The rounded edge or curvature at the corners of a hot tub cover, enhancing its durability and fit.
  21. Cover Lifter: A device that assists in lifting and storing the hot tub cover when the hot tub is in use.
  22. Deck: The area surrounding the hot tub, often made of wood or composite material.
  23. Digital Control Panel: A user interface for adjusting hot tub settings and temperature. Also called Topside Controls.
  24. Drain Plug: A plug that seals the drain valve when not in use.
  25. Drain Valve: A valve used to drain the hot tub for maintenance or winterizing.
  26. Enzyme Cleaner: A product that uses enzymes to break down organic matter in the water.**
  27. Equipment Access: The designated opening or panel on a hot tub that provides easy access to its internal components for maintenance and repairs.
  28. Filter: A component that removes debris and particles from hot tub water to keep it clean.
  29. Filtration Cycle: The period during which the hot tub’s water is filtered to remove impurities. Interchangeable with Circulation Cycle.
  30. Footwell: The lower portion of the hot tub where bathers can place their feet while seated.
  31. Foundation Pad: A supportive base or platform, often made of concrete, gravel, or interlocking pavers, on which a spa is placed to ensure stability and weight distribution.
  32. Freeze Protection: A system that prevents water from freezing and damaging the hot tub.
  33. Freeze Sensor: A sensor that detects low temperatures and activates freeze protection.
  34. Gecko: A leading manufacturer of electronic control systems and key components for hot tubs, known for their advanced technology and reliability.
  35. GFCI (Ground Fault Circuit Interrupter): A safety device that cuts off power to the hot tub if an electrical fault is detected.
  36. Gasket: A rubber or silicone seal used in various hot tub components to prevent leaks.
  37. Heater: A component that maintains the desired water temperature in the hot tub.
  38. Heater Bypass Valve: A valve that diverts water away from the heater for maintenance.
  39. Heat Blanket: An insulating cover placed under the hot tub cover to retain heat.*
  40. Heat Exchanger: A component that transfers heat from the hot tub’s heating element to the water.
  41. Hydrojet: A powerful water jet designed for targeted hydrotherapy massage.
  42. Hydromassage: The therapeutic use of water pressure and jet action for massaging and relaxing muscles in a hot tub.
  43. Hydrotherapy: The therapeutic use of water jets and buoyancy in a hot tub.
  44. Inlet Fitting: An opening where water is drawn into the hot tub for circulation.
  45. Jets: Nozzles that emit water and air to create hydrotherapy and circulation in the hot tub.
  46. Jet Face: The visible part of a jet that directs water flow and massage action.
  47. Jet Pump: A high-speed pump responsible for jet propulsion in the hot tub.
  48. Low-flow Error: A warning message indicating restricted water flow in the hot tub.
  49. Microfiltration: An advanced filtration system that removes particles as small as 1 micron.*
  50. Microorganisms: Tiny organisms such as bacteria and algae that can proliferate in hot tub water.
  51. O-ring: A rubber seal used in various hot tub components to prevent leaks.
  52. Ozonator: A device that produces ozone gas to help sanitize and clarify hot tub water.
  53. Ozonator Check Valve: A one-way valve that prevents water from entering the ozonator.
  54. pH Level: A measure of the acidity or alkalinity of the water, with an optimal range of 7.4-7.6 for hot tubs.
  55. pH Increaser: A chemical used to raise the pH level of hot tub water.**
  56. pH Probe: A sensor that measures the pH level of hot tub water electronically.
  57. pH Reducer: A chemical used to lower the pH level of hot tub water.**
  58. Plumbing Manifold: A system of pipes that directs water flow to various hot tub components.
  59. Pre-Filter: A device used to remove impurities from tap water before filling the hot tub.
  60. Pump: A device that circulates water through the hot tub’s filtration and heating systems.
  61. Redox Potential (ORP): A measure of the oxidation-reduction potential in the water.
  62. Rotationally Molded Plastic: A durable and cost-effective material for spa shells, created by heating and molding plastic pellets into the desired shape.
  63. Saltwater System: An alternative water treatment method that uses a salt chlorinator to generate chlorine from salt in the water.*
  64. Sanitizer: A chemical used in hot tubs to eliminate bacteria and contaminants, ensuring safe water conditions.
  65. Sanitizer Residual: The amount of sanitizer remaining in the water after disinfection, ensuring continued water safety.
  66. Semi-Inground: An installation method where the tub is partially set into the ground, providing a more integrated and accessible design.
  67. Skirt: The decorative panels or covering around the exterior base of the hot tub. Interchangeable with Cabinet.
  68. Sump Pump: A tool for quickly draining water from the hot tub in case of a flood.*
  69. Spa Aromatherapy: The use of scented oils or crystals to enhance the hot tub experience.
  70. Spa Cap: A protective cover for the hot tub cover, shielding it from weather damage.
  71. Spa Cover Clips: Clips or straps that secure the spa cover during high winds.
  72. Spa Cover Lifter: A device that assists in removing and replacing the hot tub cover. Can be manual or automatic.
  73. Spa Cover Seal: A gasket or seal that helps create an airtight seal when the cover is closed.
  74. Spa Pack: The control system that manages the hot tub’s functions, including temperature and filtration.
  75. Spa Pillow: Cushions designed to support the head and neck while in the hot tub.
  76. Spa Rail: A safety handrail for assisting with entering and exiting the hot tub.
  77. Spa Scents: Aromatherapy products designed specifically for hot tub use.**
  78. Spa Shell: The interior surface or tub of the hot tub, typically made of acrylic or other durable materials designed to hold and contain the water.
  79. Spa Stereo System: An audio system designed for use in or around the hot tub.
  80. Spa Steps: Platforms or stairs used for safely entering and exiting the hot tub.
  81. Spa Vacuum: A handheld vacuum designed to clean debris from the bottom of the hot tub.
  82. Spa Waterfall Valve: A control that adjusts the flow and intensity of a waterfall feature.
  83. Stainless Steel: A durable and corrosion-resistant material used in various components of a hot tub, such as jets, frames, and hardware, known for its longevity and resistance to staining.
  84. Suction Fitting: An opening that draws in water for circulation and filtration.
  85. Thermometer: An instrument used to measure the water temperature in the hot tub.
  86. Timer: A device that controls the duration of specific hot tub functions, such as filtration.
  87. Total Dissolved Solids (TDS): The total amount of dissolved substances in hot tub water, can affect water quality.
  88. Turbidity: The cloudiness or haziness of the water caused by suspended particles, which can affect water clarity.
  89. UV-C Bulb: The ultraviolet lamp used in UV-C sanitization systems.
  90. UV-C Sanitizer: A system that uses ultraviolet light to disinfect hot tub water.
  91. Venturi: A device that introduces air into the water stream to enhance jet performance.*
  92. Water Balancing: Adjusting the levels of various chemicals to maintain proper water chemistry.
  93. Water Feature: Decorative elements like fountains or waterfalls in the hot tub.
  94. Waterline: The area where the water meets the interior surface of the hot tub.
  95. Waterline Cleaner: A product that removes oils and residue at the waterline.
  96. Water Chemistry: The precise balance and quality of chemicals in hot tub water to ensure safety and clarity.
  97. Water Softener: A device or chemical additive used to reduce water hardness. Not recommended for spas.
  98. Water Tests Kit: A set of tools and chemicals used to measure and monitor water chemistry.
  99. Waterfall Valve: A control that adjusts the flow and intensity of a waterfall feature.
  100. Winterization: The process of preparing and protecting a hot tub from freezing temperatures and potential damage during the colder months.

* Please be aware that the following items are not offered for sale by Artesian Spas.

** We do not provide direct endorsements or insights regarding these items due to liability considerations.