Most hot tub manufacturers recommend changing the hot tub water every 3-4 months depending on use. If the water is maintained during that time, emptying the hot tub and refilling it every 3 months is a good practice.
The reason for this is that TDS accumulates in the spa even though chemicals are maintained and the filter is cleaned regularly.
TDS means total dissolved solids. For example, if you keep adding sugar to a cup of coffee, the water gets saturated after a while. The same goes with the hot tub. After a time, the chemicals may get supersaturated. You then lose effectiveness of the existing chemicals and lose money. That is why we change the hot tub water every 3-4 months.
Drain the spa, wipe it down and start over.Use a pre-filter attached to the hose and First Step when refilling the spa and you are good to go!
Draining a hot tub does not have to be a chore. See the Hot Tub Outpost video on how to drain a hot tub. We recommend using an external submersible pump, but get the kind that goes almost all the way down to the floor to avoid excessive bailing. Then just let the pump drain out the spa in about 15-20 minutes instead of waiting hours for the gravity drain that is featured with most hot tubs. Some hot tubs do not have a drain at all, so the choices there are to use reverse gravity through a garden hose or get a submersible pump that is ideal for draining hot tubs.
When draining the spa, it is a good idea to wipe down the acrylic, clean the pillows and cover and wash out the filter.
Draining a Hot Tub in Northern Climates
For those hot tubs up north, it is best to time the winter draining/cleaning for around the end of November which can then carry the spa through the beginning of March. Nobody wants to out fussing with the garden hose when it’s 20 below. Besides that, the garden hose if left outdoors, it will turn into an ice-filled, unusable hose. It is best to store the hose in the basement or garage when not in use. Also good to remember to shut the exterior water back off when done filling the hot tub in February or March because there could still be more freezing weather into April.
When to Drain a Hot Tub Sooner
If the spa is getting heavy use and the chemicals are not maintained regularly, it may be best to drain and refill even if it has only been 2 months since the last water change.
Similarly, if the water is foaming excessively, a squirt of foam-down will help keep the foam away while you are trying to use the spa, but it may keep coming back due to excessive oils, lotions or shampoos that were carried in through bathing suits or hair.
How to Extend the Hot Tub Draining Intervals
Showering before getting into the spa can help limit the amount of shampoos, soaps, lotions and oils that enter the spa water. This can extend the time the hot tub can be used in between water changes. Adding a coagulant to the water can help bind up these oils and soaps so they end up in the filter. Cleaning the filter more often helps reduce foaming and buildup in the water. Try a product like Spa Breeze Protect sold at Hot Tub Outpost. This is a stain and scale preventer and water clarifier that bind the particulates in the water for clear, clean water.
Start with a pre-filter which filters out some garden hose water impurities. Add a bottle of First Step by Spa Breeze sold at Hot Tub Outpost. If you use bromine instead of chlorine as the main sanitizer, then add a pouch of Brom Start (available in 2 ounce pouches) to quickly establish a reserve of bromine in freshly filled hot tubs. This way you don’t have to wait a day or two to get in the water until the tablets dissolve enough to establish a proper bromine reserve in a newly filled spa.
See the M-W-F program for maintaining a hot tub and visit www.HotTubOutpost.com for all your hot tub chemical needs.