How often should I change the water in my hot tub?
In a typical situation, you should completely drain and refill your hot tub every 8-12 weeks. The time between changing the water in your hot tub depends on your usage. Below is a mathematical equation to help you figure out when you should change your water.
First, take the total number of gallons your hot tub will hold and divide it by 3. Take this result and then divide it by the number of bathers you will have in your hot tub every day. The final number you get will be approximately how often you need to change the water in your hot tub.