When to drain your hot tub

How often should I drain my hot tub?

Draining and refilling your hot tub periodically is important for keeping the water clean and also preventing damage. When you don't change the water, it becomes improperly balanced and can begin corroding the hot tub. Not to mention, nobody wants to soak in old, dirty water. By draining and refilling with fresh water on a regular basis, you'll ensure your hot tub is clean, clear and safe.

But the question is: how often should you do it?

With average use, your hot tub should be drained and refilled about once every three or four months. But since everyone uses their hot tub differently, the answer can vary based on how many people use it and how often.

Hot tub manufacturers like Jacuzzi offer some handy tips for figuring out when to drain and refill. One common method uses simple math:

"Divide the number of gallons of spa water by the number of bathers who usually use the tub. Then divide that number by three to figure out how often you should go through the process."

For example, if your hot tub holds 450 gallons of water, and just two people use it every day, then 450 divided by 2 = 225. And then 225 divided by 3 = 75. So you would change your water about every 75 days.

But remember, that implies that you and another person are using the hot tub every day of the week. If you're not, then you can probably go longer without draining. However, even if no one has used the hot tub for a few months, the water still needs to be changed.

Here are some other signs it's time to refill:

  • Foamy and Funky Water
    The usual bubbly goodness is okay. But if the water's starting to look foamy, try adding your antifoam solution. No change? Then it's probably time to change the water.
    The same goes for any other funky, filmy or discolored water. If it doesn't look like it did when you last refilled it (clean and clear), then it needs to be changed ASAP.
  • What's that smell?
    Sometimes, you don't even need to look at the water to know something's not right. If you notice an unusual smell when you lift the cover or get inside the hot tub, then chances are you're way overdo for a refill. The teams at Jacuzzi write, "Any out-of-the-ordinary smell is a cry for fresh water." Drain, refill, rejoice.
  • Check the calendar
    When was the last time you drained and refilled? It's a good idea to mark each refill on your calendar (digital or paper), so that you can keep track of your ongoing maintenance. It it's been a few months, now is the time to change the water.