Ah, the joys of having a hot tub, but then you get to thinking – how long has it been since I’ve changed my hot tub water? Have I ever changed it? How often should I change my hot tub water? I’m glad that you asked because if you don’t change the water in your hot tub you are not going to be happy.
Why Should I Change the Water in My Hot Tub?
Your hot tub has a pump so that the water filter can filter the water and during that time the water gets its dose of chemicals and sanitizer. This is the same as a swimming pool. The difference is a swimming pool doesn’t need to be drained and then filled again. Confused? Why does one need it and not the other?
#1 – A hot tub has a much smaller amount of water than your swimming pool but most of the time the same amount of people are going to be hopping in and enjoying it.
#2 – The temperature makes a difference and because your hot tub is at a temperature that is much higher than a swimming pool that has an effect on what needs to happen with it in order to keep the water clean.
The chemicals and filter are either going to remove a lot of the impurities or oxidize them when they get into the water of course, but it isn’t going to get all of them. Just think about all of the body oils, sweat, and soaps that get into the hot tub. Because of this your water will become foamy, cloudy and may even begin to have a smell. Yuck!
How Do I Know When to Change the Hot Tub Water?
Make sure you are testing your hot tub water often so you don’t have to get to the smelling and foamy look. You can get a TDS test strip to put into your hot tub to see if it needs to be changed.
If you just don’t feel like going to get a TDS test strip you can use a formula to figure out if it needs changing. First, you need to know how much water you have in your hot tub. If you have a 4 seat hot tub you may have around 1250 liters of water in the hot tub. You can call the manufacturer if needed so you can see what the exact volume of your make and model is in case you don’t already have the information.
After that, you need to have the “bather load” of your hot tub. Meaning how many people are able to use it and how often they are able to use it. Now you want to take the liters of water, divide it by the average number of people in the hot tub for 20 minutes each day and then divide it by 12. This is going to give you the number of days you can go without changing the water. Most of the time you are going to get about once every 3 months.