Understanding when to change the water in your hot tub can be a bit challenging; there are two main factors:
1) Does the water demand it? This is indicated by several factors:
- Is the TDS (total dissolved solids) level high? Usually 2500-3000 or above; this is something we test for at Purewater, or you can purchase a TDS meter.
- When did you last change the water? Under normal usage (2-3 adults soaking 2-3 times a week for 15 to 20 minutes, spa at 102 degrees) a water change every 3-4 months is usually necessary. If you change these variables (keep the spa much hotter, go for longer soaks, etc.) you need to change the water more often.
- Persistent water quality issues? From foaming to cloudiness to off-odors, if the water is becoming less appetizing, it is often EASIER and CHEAPER to change the water versus pouring a ton of chemical into the hot tub.
2) Is it an opportune time? Working outdoors to drain and fill a spa is much easier when the temperature cooperates! Sometimes it pays to do a water change before it is absolutely necessary simply because the weather allows.
We thought it would be helpful to send along some information to help you out with this important maintenance task, should you choose to go for it!.
STEP ONE: CLEAN YOUR FILTERS
Remove the floating chlorinator, and anything else floating in the spa, if you have one. Then remove your filters, rinse, and put in a large bucket with clean, warm water and Aqua Finesse 2 Hot Tub Filter Cleaner tablets or Natural Chemistry Filter Perfect.
PRO TIP: For improved filtration, give cleaned filters a chance to dry completely before installing them again. This improves their ability to trap fine particles. Many spa owners keep a spare set for this purpose. If your filters are looking worse for wear (fraying, or look really dingy after soaking) consider purchasing new ones.
STEP TWO: ADD TUB CLEANING PRODUCT
Close all air valves. Add 1 Aqua Finesse SpaClean tablet or Natural Chemistry Spa Purge. Over the course of a few hours, keep popping out every 30 minutes or so to cycle the pumps on again. Be sure to open all the diverters and jets, so that all waterfalls and jets have water running through, to clean all the lines. This ensures a good cleaning of all surfaces and gets at unseen debris inside all pipes. Try and do 3 to 4 pump cycles with the lid off. If it gets too late to finish the job on day one, make sure you close the lid overnight, and run a couple of cycles the following morning.
STEP THREE: DRAIN TUB
Turn off breaker to hot tub and drain it with the gravity drain, or with a submersible pump. As the tub drains, you will need to bail or scoop the water from the higher areas, such as seats, into the center foot well of the tub. As the water level drops wipe down the hot tub surface with a clean, damp rag. If you have any hot tub ring, clean with Natural Chemistry Clean & Perfect, and rinse off with a hose.
PRO TIP: Check where you are draining to! Spas contain enough water to do some damage, and with ground often frozen in winter, you want to be sure that water is running well away from your foundation. If you plan to drain the spa, stop adding chemicals a day or two ahead. If the chlorine/bromine level is below 2 PPM when you drain, the water is essentially harmless to grass and plants.
STEP FOUR: FLUSH AND RINSE
Run clean water down the filter lines and into any accessible jet openings. This helps force any loosened debris out. When you have finished rinsing and flushing drain the hot tub again.
PRO TIP: Don’t let the perfect be the enemy of the good. You will never get 100% of the water out of the tub. As you rinse and flush you will dilute any sediment remaining. If you still see lots of foam or sediment, keep rinsing with fresh water while the drain is open or the sump pump running, until the water left in the spa looks pretty clear; this is “good enough”. It is just fine to have an inch or two of relatively clean water remaining in the lowest part of the tub. Also keep an eye on temperatures. If you start to notice ice building up on the interior of the hot tub as you are rinsing, stop cleaning and start refilling the spa, so you can turn it back on.
STEP FIVE: CLEAN THE COVER AND PILLOWS
Clean the inside and outside of your hot tub cover with Natural Chemistry Clean & Perfect, then rinse well. If you have any black spots or pink stains on the cover, clean with a mild water/bleach solution (10:1) to remove. Pop out the pillows, if your hot tub has any, and perform the same cleaning.
PRO TIP: To keep your cover and other soft surfaces shiny and UV protected, use Formula 303 Protectant on the outside of your cover.
STEP SIX: RINSE & INSTALL FILTERS
Remove filters from cleaning solution and rinse very well with a Filter Flosser, install in the hot tub. If you have a disposable filter in your filter mix, make sure you replace it with a new one.
Remove filters from the cleaning solution and rinse very well with a Filter Flosser, then install in the hot tub. If you have a disposable filter in your filter mix, make sure you replace it with a new one.
STEP SEVEN: TIME TO REFILL
Once the tub has drained, start refilling your spa. If you opened the drain, be sure to close it again, ensuring that any gaskets in the cap are still present and haven’t fallen out. Put the hose in skimmer area (where you install the filters) and let the tub fill. You can fill with warm water, approximately 60% hot, 40% cold, but do not fill with just hot water. Once tub is full, turn on the breaker and let the tub start its priming cycle. Check the owner’s manual for details. Note that, having let the water out of the lines, some of the pumps may have a hard time priming again. You can cycle the pump on and off a few times, or check our video on clearing an air lock, if the problem persists.
STEP EIGHT: ADD CHEMICALS
Once the tub water is warm, add 20gms of ChlorAid per 1000 L of water. For example, a 1,500 L spa would need 30 gms of ChlorAid. 1 level teaspoon = approx. 5 gm. If you have fresh fill instructions for your hot tub, add the balancers 20 minutes after adding the ChlorAid. If you don’t have fresh fill instructions, wait 24 hours after adding ChlorAid, and bring in a water sample to Purewater for your free test.