Other aspects that create different prices are materials and components that are used in manufacturing. The most expensive part (of most) hot tubs is the shell (interior surface). For instance, most brands use forms of plastic, or ABS or cast acrylic sheets for their hot tub shells.

If you use your spa often, you may find you need to change your water more frequently. However, even if you're a weekend warrior, you should be changing your water every three months, regardless. Additionally, you may discover some water issues arising that may require you to drain your spa and start fresh again.

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.

Always pay close attention to water hygiene when using lake or seawater and if you have any suspicions regarding the cleanliness, you should change the water and clean the hot tub. It is recommended to change the water every one or two days after normal family use.