How Often Should I Drain My Hot Tub?

How Often Should I drain my hot tub

Periodically draining and refilling your hot tub is important for keeping the water clean. Draining and rebalancing also prevent damage as improperly balanced water can lead to corrosion. To keep you and your hot tub healthy, you’ll occasionally need to drain your spa and start over.

Signs that it’s time to drain and refill your hot tub: 

  • Foamy water: If antifoam agents such as Spa Life Foam Away don’t reduce the foam in your tub, it’s time to change the water. 
  • Filmy or discoloured water also signals a need for a change. 
  • Smelly water: If you notice an unusual odour, you’re due for a drain and refill. 

Factors that affect when to change the water in your hot tub:


  • Initial water quality: 
    • Hard water/well water is naturally pure and without additives. However, well water often has high levels of metals (copper, lead), microorganisms and minerals (calcium, magnesium). It may leave a residue, which, though not dangerous, can be annoying. Homeowners with well water will need to take advantage of scale defence products in order to extend the time before they need to drain and refill. Eco One Monthly and Spa Marvel reduce scum lines while Super Clarifier helps reduce scum lines and metal build-up.
    • Soft water is treated and has little if any calcium and magnesium. It can corrode metal surfaces inside the hot tub. The key to extending the time before you need to drain and refill is to increase the water hardness by adding calcium chloride with a product such as AquaCal.
  • The quality of your chemicals: To extend the time between water changes, use the right chemicals and use high-quality chemicals. Inferior chemicals leave behind solids (fillers, binders, glues) which cause cloudy water and require more chemicals to fix the problem. High quality chemicals not only leave behind fewer solids, they can be used in smaller quantities and still produce good results. 
  • Improper use of chemicals: Poor water chemistry, over correction of the chemicals and the addition of substances you don’t actually need can all contribute to shortening the expected lifespan of the water in your hot tub.
  • The spa filtration/purification system: The higher the quality of your spa’s filtration/purification system the longer you can go before you need to drain and refill. American Whirlpool spas utilize a four-step cleaning system and dual sanitation features which make the waters of these spas safe for your family’s usage. This water treatment system is used to sanitize drinking water all over the world! 
  • Usage: Whether the spa is used occasionally or daily and how many people use the spa will determine how often you need to drain and refill. Do you shower before jumping in the hot tub? This will reduce your need to drain. Do you have the occasional hot tub party on the weekends? This may speed the need for a change of water. 
  • Location: Is your spa located under or near trees? Is it surrounded by mulch, dirt or gravel? Where your hot tub is located can affect how much debris enters it and how often it will need to be drained.
  • If you add scents and oils to your hot tub you’ll likely increase the frequency that you need to drain and refill as both oils and salts can build up in the water over time. 

How often you need to drain and refill your hot tub depends upon how well you maintain your water, how many people use the tub, how often the tub is used, where the tub is located and the quality of chemicals added. Watch for the signs that indicate it is time to drain and refill your spa. Mark your calendar each time you change the water. You’ll quickly become aware of just how often your individual hot tub will need draining and renewing.  

Looking for quality chemicals to reduce how often you need to drain and refill your hot tub? Need help making a hot tub purchase? The experts at RnR Hot Tubs and Spas are here to help. With over 200 hot tubs available for sale, we’re the spa shop for you. Owned by service professionals with over 30 years of experience, we help make your hot tub purchase exceptional. Please call 403-203-0860 to set up an appointment.


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