Hot Tub or Spa has a water heating system and comes handy during winter and fall when the temperature is cool and snow falling, making swimming pools without pool heaters a no go zone due to freezing cool water and ice.
While Hot Tub chemicals are the same chemicals used to maintain swimming pools, its maintenance routine and how hot tub works is different from that of a pool; for example hot tub maintenance and cleaning, monitoring and maintaining chemical levels, and water circulation.
A). Hot Tub/Spa Maintenance and Cleaning
There are a few hot tub maintenance measures you need to take on a daily, weekly, quarterly, and annually to make sure your spa is always clean and usable all through the cold seasons, whether an indoor or outdoor Spa.
Outdoor spa are prone to getting dirty with leaves or windblown trash. These can be cleaned using a special net or hand skimmer just the same way it's done in a swimming pool.
1) Cleaning Spa Jets and Shell
Spa come with Spa Jets and Shell for water circulation; make it a weekly routine to clean Spa Jets and Shell using a soft sponge with white vinegar.
To avoid mildew in your hot tub, you can use a less stronger 10% chlorine bleach like Kem-Tek sodium hypochlorite to clean the inside and Shell of your hot tub, wipe it down thoroughly for a cleaner hot tub and proper sanitation effect to keep mildew at bay all the time.
2) Cleaning Waterline
Hot Tub Waterline edges also tend to form Scum-line when not cleaned, you can use soft sponge with white vinegar to scrub off the scum line on your hot tub's waterline as well after every use.
Hot tub Waterline can be scheduled for a daily/weekly cleaning routine depending the usage, this is also helps keep your water clean.
3) Maintaining Clean Water
To keep your water clean, make sure you sanitize your spa using chlorine when free chlorine(FC) level drops below the recommended range of 3-6ppm. Find more about chlorine and other chemicals in 'Hot tub chemistry' section below.
Moreover, since hot water in your tub will extract oil, lotion, soap or makeups from users, oily stuff will float on top of your water and this will definitely clog your filters if don't take action after every bath.
You can use Scum Balls trick to remove oil and all the dirt from your Spa water; fluffy tennis balls can do the trick. Put a few scum balls or fluffy tennis balls in the skimmer and drop a few more balls in your hot tub to float on water and collect all the dirt left after a bath.
Also, to maintain clean water and avoid making your water dirty fast, clean the waterline and seats very often.
How to Clean Hot Tub/Spa Filters
Just like the Kidney is important in cleaning blood in human, Hot Tub filters are equally important in cleaning your water and you need to take good care of your filters.
Make it a routine to drain your spa every three to four months for a thorough cleaning of the spa filters.
After draining and cleaning your Spa and filters, be very careful when re-filling to avoid unnecessary overflow, the best way to avoid water overflow is to set a timer.
To clean your hot tub filters and and increase efficiency and lifespan of your filters, perform the following at least ones in 3-4 months:
1) Rinse Hot Tub/Spa Filters
The first one is rinsing the filters using warm to hot water to remove oily stuff if you have not been using tennis balls trick, otherwise, rinse the filters with an outdoor hose, the more you use the hot tub, the more often you need to rinse the filters.
2) Spray Hot Tub/Spa Filters
Secondly, your hot tub filters need some spraying using hot tub filter cleaner to loosen and remove oil, lotion, makeups and more that have stuck on the filter cartridges, you will need to spray the filters more often if your spa is ever busy to improve lifespan of your filter cartridges.
3) Soak Hot Tub/Spa Filters
Last but least, hot tub filter soaking is necessary every time you drain and re-fill water. To soak the filters, use a powerful Spa filter soak and cleaner that will loosen strong dirt and make the filters more effective.
However, when the filters are done and won't clean up even if you soak in the cleaning chemical, it is time to buy new hot tub replacement filters and replace the old ones.
Remember to flush the spa lines after every hot tub draining, however, this can be done annually alongside major repairs done by a technician like fixing broken hardware, electrical wires, hot tub cover, and more.
B). Hot Tub/Spa Chemistry
Before adding chemical in your hot tub for the first time, you need to carry a complete water analysis by testing the water to know the chemical levels especially pH, Alkalinity, Chlorine (sanitizer) and Stabilizer (Cya).
To measure accurate chemical levels in your Spa, you can use a reliable pool water test kit like LaMotte ColorQ Pro or Taylor Technologies test kit to measure and establish the exact chemical levels in your hot tub before adding any chemical.
Remember to test your hot tub chemical levels very often just like we do in pools without water heating system. This is a very important spa maintenance procedure because you will know exact chemical level adjustments to make to keep your water clean and healthy all the time and avoid skin problems like hot tub rush.
1. Chlorine (Sanitizer)
Chlorine is one of the most important chemicals in a hot tub and just like in a swimming pool, chlorine sanitizes your spa water better than non-chlorine hot tub oxidizers out there.
A stronger liquid chlorine with 10% - 12.5% available chlorine is the best sanitizer to use in a hot tub to keep your hot water sanitized longer than when you use a regular bleach of 5% - 8% available chlorine.
However, when adding chemicals for the first time in a new hot tub or drained and re-filled spa, it is advisable to use stabilized chlorine particularly dichlor that comes with Cyanuric acid for the first few days before starting to use liquid chlorine.
A new/refilled Hot tub requires a higher Free Chlorine range of up to 6 ppm, and this needs a stronger and stable chlorine like dichlor or trichlor .
For the first few days you will be adding stabilized chlorine in your spa to maintain it at 6ppm, measure Cyanuric acid (Cya) level frequently and shift to liquid chlorine (non stabilized chlorine) when stabilizer or Cyanuric acid level hit 30ppm.
Once your cyanuric acid level gets to 30ppm, you shift to using liquid chlorine, which is best for maintaining FC level between 3-6ppm and will not raise your Cyanuric acid level.
Continue testing and maintaining your free chlorine level at this range using liquid chlorine and you will not have chlorine-stabilizer issues in your hot tub or spa. Here is more detailed article on how to shock your spa or hot tub and the best sanitizer to use.
Just like a swimming pool, combined chlorine or chloramine in a hot tub or spa should not go beyond 0.5ppm or your water will appear cloudy and dirty. Use this Chlorine/Cya chart by TFP to know the exact level to maintain your FC and Cyanuric acid in your hot tub or spa.
2. pH Level
Just like we do in pools, hot tub or spa needs pH between 7.2 - 7.8. Use pH Plus to raise your pH level in your hot tub when it falls below the recommended range, and use Muriatic acid to lower pH when it goes above 7.8, pH tends to increase a lot in a hot tub, spa, or pool due to aeration. Note that Muriatic acid also lower Total Alkalinity when added in a hot tub, spa, and swimming pool.
pH below 7.2 is very acidic and will eat away hot tub or spa parts causing damage. On the other hand, higher pH than 7.8 is destructive since it will cause Scale on hot tub/spa equipment, especially the heater or heat exchangers causing damage that might need replacement.
3. Total Alkalinity(TA) Level
Alkalinity is one of the most important chemicals to watch both in a swimming pool and hot tub or spa because if TA goes out of range, it will affect the pH since it acts as a pH buffer. High alkalinity will definitely escalate pH levels so fast and you don't want that.
4. Calcium Hardness(CH) Level
One of the most common problems in a hot tub or spa is foaming. We use Calcium in a hot tub or spa to avoid foam. So, if you been noticing foam in your hot tub, spa, or swimming pool, check your CH level and balance it as appropriate.
Keep Calcium Hardness level in your hot tub above 100ppm all the time. Remember, a hot tub or spa just like a swimming pool have some ceramic material and low calcium may cause damage to these parts made of ceramic or cement. On the other hand, a high CH level may lead to calcium scaling in your hot tub.
Use Calcium Hardness Increaser to raise CH level when lower than 100ppm, however, you need to be very careful not to add excess calcium since the only way to lower Calcium Hardness in a hot tub, spa or pool is drain and re-fill your water.
C). Hot Tub/Spa Water Circulation System
Water circulation is one of the most important processes making a pool, hot tub or spa water clean and fresh as water is forced to pass via filter cartridges that remove dirt and small particles making the water cloudy.
In most cases, a hot tub or spa has an auto-circulation system and you can schedule water circulation once or twice a day for 15-20 minutes, filtering all the debris from your hot tub, remember, the more you circulate the water, the cleaner and fresher your spa/hot tub water will be.
Heavily used spa or hot tub can be circulated twice a day for cleaner water. If your hot tub or spa has no auto-schedule system and you can't schedule circulation, make sure you manually circulate and refresh the water for 15-20 minutes a day.