Hot Tub Chemical Guide: Spa Water Treatment


Each weekend and when refilling spa water:
Determined by using a test strip or drop kit:

1. Adjust alkalinity between 80 -120
2. Adjust pH between 7.2 – 7.8
3. Add Stain & Scale Control (if necessary)
4. Shock – Leave cover open about an hour
5. Adjust chlorine level between 3-5 ppm
As a general rule shock your spa weekly or after every other use, but always after heavy use.


Adjust chlorine level between 3-5 ppm.


1. Adjust chlorine level between 3-5 ppm.
2. Add Spa Perfect.

Every month:

Clean filters – rinse with hose.

Every other month:

1. Clean filters – soak or spray with filter cleaner – rinse with hose.
2. Clean and condition the top of your spa cover.


1. Drain, clean, and re-fill your spa every 3-4 months; every 6 months if using a Vision Cartridge.
2. Install a new Vision Cartridge every 6 months.
3. Replace the Ozone Generator every 18-24 months.
4. Install filter(s)


See our “Easy Spa Water Care”guide for complete info!

Total Alkalinity:

Alkalinity is an important measure of the water’s ability to resist pH swings. (Ideal Range = 80-120).

  • Below 80 – pH “bounce” is common. pH becomes unstable and difficult to keep in the ideal range.
  • Above 120 – pH resists adjustment .


pH is the measure of acidity or alkalinity in the water. Itchy skin and damage to the spa heater are common when pH is either too high or low. (Ideal Range – 7.2 – 7.8)

  • Under 7.2 – Acidic and corrosive to spa equipment
  • Above 7.8 – Chlorine is not effective
  • Above 8.2 – Bromine is not effective

Stain & Scale Control:A weekly dose in areas with hard water or copper and iron content is recommended. Regular use of “Stain & Scale Control” prevents stain and scale buildup caused by excessive metals & minerals, extending life of your spa heater.

Shock TreatmentShock Treatment:Quickly oxidizes (burns), common contaminants out of the water such as bacteria,lotions, cosmetics, etc. Shocking helps keep water clear and clean.

  • Shock when refilling your spa to remove bacteria residing in the hose or plumbing.
  • As a general rule shock your spa weekly or after every other
  • use, but always after heavy use.
  • Leave your cover open at least 60 minutes to allow the “bad stuff’ to evaporate.

Sanitizer:Maintaining an adequate level of sanitizer in the water is critical. Warm water presents a fertile environment for the growth of bacteria and virus. This growth is prevented when sanitizers are continuously maintained.

  • Chlorine is quick to dissolve and begins working immediately. (nearly pH neutral, it has little effect on the pH or alkalinity)
  • Bromine is a good solution for those who use their spas occasionally and also eliminates the need to shock.

Nothing is more inviting than the warm, crystal clear water of a well maintained spa. We all want healthy clean water, but don’t always know how to get it. Luckily, balanced water is easy to maintain, and once you learn the essentials you can establish a routine that fits your lifestyle. Your unique routine reflects both the amount of time you use your spa, and the number of people who share it with you. Appropriate maintenance for a spa that’s used by one or two people a couple of times a week is much different than one that’s used to entertain a group of people for an afternoon.

A spa is made to enjoy, whether you are alone or with friends and family. Use this easy to follow guide and learn how to adjust your spa water to keep it clean and healthy. Whether you’re a new owner or have been enjoying your spa for years, we’ve included valuable tips and information to keep your investment operating for years to come.

Testing and Adding Chemicals… for Dummies

Routine water testing is an important part of spa maintenance and should never be overlooked. Test kits are the most accurate way of testing your spa water, but they are also the most time consuming. An easier alternative are test strips, which if stored properly, work almost as well.

Part of keeping your spa water healthy and clean involves testing the water regularly to ensure chemicals are balanced properly. Some products, like sanitizers, keep your water clean and healthy by killing harmful bacteria; while others maintain important pH or alkaline levels.

Remember, good water care becomes easier as you discover the best routine for your actual spa use.

Quick Tip:

When adding chemicals, start by activating the high speed pump and after a few minutes, switch to low.

Why is Balanced Water Important?

If you want soft, silky water, balanced alkalinity and pH are critical important first steps. Why? Because when those readings are out of balance your sanitizer won’t work properly. Plus, unbalanced water causes dry, itchy skin and can even damage your spa equipment.

Test alkaline and pH levels weekly.

Alkalinity pH
(Ideal Range: 80-120 ppm) (Ideal Range: 7.2-7.8 ppm)
If Alkalinity is too low:

  • pH “bounces”, moving up and down in large swings
  • Reduces heater life through scaling or corrosion
If pH is too low:

  • Causes dry, itching skin
  • Chlorine dissipates quicker
  • Reduces heater life through corrosion
If Alkalinity is too high:

  • pH adjusts slowly
  • Reduces heater life through scale formation
If pH is too high:

  • Contributes to cloudy water
  • Causes dry, itching skin
  • Chlorine stops working

Should I Use Chlorine or Bromine?

There are several different types of sanitizing agents on the market; the two most popular are chlorine and bromine. Both are highly effective – it’s simply a matter of choosing the regimen that works best for your specific needs and budget.

There are three basic reasons to sanitize spa water:

  • Kill bacteria and germs
  • Oxidize organics like oils, lotions and soaps
  • Leave a residual sanitizer in the water continuing to protect against growth of microorganisms.

Expect to test and add sanitizer 2-3 times per week.

Chlorine (Ideal Range: 3-5 ppm) “Granular Sodium-dichloro,” more commonly known as “chlorine “is the most common and economical sanitizer available. It’s user friendly, convenient and readily available. (Always choose chlorine granules with a Sodium-dichloro level of at least 99%.) Chlorine absorbs quickly and works instantly, has no negative effect on pH or alkaline levels, and can even be used to shock spa water. Nevertheless, it needs to be replenished frequently and when not maintained adequately, has an unpleasant smell associated with it. Remember, chlorine pool tablets are too strong for a spa and will cause itchy, dry skin, or even damage the interior shell of your spa

Bromine (Ideal Range: 3-5 ppm) Bromine can be purchased in either one inch tablets or granular form. Both methods offer a convenient method of sanitizing your spa. As an added benefit, there is no classic chlorine type smell associated with bromine.

Bromine Tablets pH
  • Dispensed using a floater
  • Dissolves slowly at a constant rate
  • Refill when the tablets have eroded.
  • Takes time to create the proper residual level.
  • Requres floater adjustment for proper levels
  • Added directly to the spa water, (similar to chlorine)
  • Dual-purpose product: sanitizer and oxidizer, (no need for 2 products)
  • With a low pH of 4.6, bromine requires more frequent adjustment of pH and alkalinity.

Why Should I “Shock” My Spa?

Sometimes it’s necessary to “shock” your spa water. Perspiration, cosmetics, lotions, etc. build up over time, reducing the effectiveness of your sanitizer. Because this type of waste dissolves in water, your filtration system can’t remove it. Depending on how often you use your spa, you may need to shock your water weekly, but certainly after heavy use. Luckily, spa “Shock” products are available to make the process easy, inexpensive and convenient.

Non-Chlorine Shock (Peroxymonopersulfate) The biggest advantage of a non-chlorine shock is the ability to re-enter the spa quickly, (after about an hour). Because nonchlorine shock contains no sanitizer, you’ll need to add a normal dose of chlorine or bromine granules before getting back in.

Follow the dosage instructions on the package. Run the high speed jets during this process for at least 30 minutes. Leave the cover open for 60 minutes to allow the “bad stuff” to evaporate.

Shock Xtra Combining two steps in one, Shock Xtra uses a non-chlorine shock to oxidize those things in the water that need it, and leaves a chlorine residual at the same time. Just as important, you can re-enter the spa within an hour. For no extra cost, your work is cut in half. Follow the dosage instructions on the package. Run the high speed jets during this process for at least 30 minutes. Leave the cover open for 60 minutes to allow the “bad stuff” to evaporate.

Chlorine Shock Using granular chlorine is the strongest, most effective shock method, but don’t re-enter the spa until the chlorine level has returned to the normal range as measured on your test strip. (This can take up to a full day and a half.) Follow the dosage instructions on the package. Run the high speed jets during this process for at least 30 minutes. Leave the cover open for 60 minutes to allow the “bad stuff” to evaporate.

Why do I Need “Spa Stain & Scale?”

Spa Stain & Scale protects your spa from the damaging effects of scale build-up and staining due to excessive calcium, iron, copper and other minerals.

What is “pH Anchor?”

pH Anchor softens water by removing calcium, (the cause of hard water), and maintains a comfortable, stable pH. Helps extend the life of the spa heater. In addition, pH Anchor simplifies water care – just one bottle locks in pH in most spas for up to 2 months and reduces calcium levels to prevent corrosion.

The “Calcium Hardness” reading should be:
(100-200 ppm)

Reducing the use of Spa Chemicals…

Many people would like to use less chemicals in their spas. We recommend the following 4 coordinated products in our ESP “Safe Guard System” to achieve the highest quality protection for you and your family!

Ozone Generator
Ozone Generators are widely regarded as “the” optimum water sanitizer and is used in various applications from drinking water to swimming pool purification. The most powerful oxidizer available, “Ozone” reacts 2000 times faster than chemical sanitizers. Ozone safely kills bacteria, viruses and fungus, while oxidizing lotions, oils and other contaminants. These materials are particularly difficult to trap with a traditional filter, but can be removed on contact with the Ozone Generator..

The Ozone Generator improves water clarity, reduces chemical use and maximizes bather comfort. Ozone Generators have a 1-2 year life expectancy and cannot be used as the sole sanitizer; you still need to supplement with chlorine or bromine. In addition, after heavy use, “Ozone” can be overwhelmed and your spa water needs to be “shocked” to return its proper clarity.

Vision Sanitizing Cartridge
An easy and effective supplement to both Chlorine and Ozone systems, “Vision” uses a silver catalyst to kill 99.9% of bacteria, virus and fungus on contact. “Vision” extends the life of your spa water to 6 months so you can drain and re-fill less often. For best results, change your water and install a new Vision Cartridge at the same time.

Spa Purge
Spa Purge contains natural enzymes for breaking down and removing organic waste deposits like oils, lotions and soaps from spa plumbing. Spa Purge even removes unsightly “floaties” in your water that often appear as little white specks. It’s recommended that you use Spa Purge once a year, adding it the day before draining and refilling your spa. A weekly application of Spa Perfect will continue to reduce organic buildup during normal use.

Spa Perfect
Spa Perfect reduces the demand of chemicals, making them more efficient. A weekly application of Spa Perfect, (a natural enzyme solution), continues to remove organics (oils, lotions, soap, etc.) in the spa water.

  • 100% biodegradable & hypo-allergenic
  • Reduces the use of sanitizers and shock
  • Reduces foam and waterline ring
  • Prevents filter clogging
  • Helps filters operate more efficiently
  • Prevents chemical odors
  • Safe around people, pets, and gardens

Routine Spa Maintanence

Maintaining clear, inviting water requires that every so often, you drain your spa and start again. Depending on how often you use your spa, you’ll need to change the water regularly. Usually, every 3-4 months is fine, or every six months if you’re using a Vision Sanitizing Cartridge. However, if your spa gets heavy use, you should consider changing your water more often. Every spa is different and so is the water used to fill it. If you have well water, or particularly high levels of minerals, consider using a pre-filter when filling your spa. These attach to the end of your garden hose and help remove minerals or contaminants.

The cleaner you are before stepping into your spa, the easier it is to keep your water clean. If you just exercised or worked in the yard, spa chemicals have to work overtime and will probably be used up before their job is done. Take a quick shower before enjoying your spa. There are clues that you’re water may be overdue for a change. If the water never gets quite clear, pH and alkalinity adjustments become more difficult, or you used more sanitizer than you did the previous month, you may want to change it.

Filters & Water Circulation

Filters and circulation are an important part of spa maintenance and a cornerstone to keeping clear, fresh water. If your filter does not perform properly, neither will the products you add to the water. Filters are made of a finely spun polyester fabric that traps foreign materials including leaves, dirt, lint, even body lotions and prevents them from re-entering your spa water.

The water must be circulated for the filter to work, so the longer it circulates, the more efficiently your filter works. It’s recommended you run your filter for a minimum of two hours per day to allow the system to effectively remove any particles and debris.

Cleaning the Filter

Clean your filter once every month to keep it working properly and your water looking its best. It’s easy to do and only takes a few minutes. Simply turn off the power at the GFCI, remove your filter and rinse with a high powered nozzle on a garden hose. The hose should remove most visible debris that remains in the fabric. However, you will also want to spray or soak your filter with a good filter cleaner every other month to remove lotions or oils that can’t be removed by water alone. Rinse thoroughly until the water runs clear and then re-install. Eventually, you’ll need to replace the filter, but a routine cleaning will ensure it works efficiently for up to two years.

Spa “Shell” Maintenance

Similar to your bathtub, cleaning the interior part of your spa regularly keeps it looking its best. A clean shell also protects the water, helping it stay clean longer. The perfect time to clean your spa shell is when you are changing the water. After your spa is drained completely, it’s easy to remove any dirt or film on the shell. For UltraLife® shell interiors, you may use baking soda or Soft Scrub on a damp rag. For colored shells, we recommend Spa Essentials Surface Cleaner® on a damp rag. This gel formulation will both clean and protect the acrylic finish, together.

Spa Cover Care & Conditioning

Now that you’ve spent all this time maintaining your spa, don’t forget one of the most important items for keeping it looking its best- the cover! Proper maintenance of your spa cover is important for keeping the inside of your spa protected and free of debris and protecting your investment for years to come. Washing with a mild kitchen detergent and a soft brush works fine and can save you money.

While there are lots of vinyl conditioners available, the wrong ones use an inexpensive petroleum base which can cause your cover to turn black. We recommend “303 Protectant,” a quality formulation that includes a UV 40 sun blocker to extend the life of your cover. Spa covers have a life span averaging 5 years and then styrofaom cores absorb water over time.

You will know this, because the cover will become heavy and difficult to maneuver. Using an EZ lifter helps to protect the core from the excess stress of lifting your cover.

These instructions are for informational purposes only. Easy Spa Parts does not guarantee that following these instructions will resolve your specifi c spa condition, nor does Easy Spa Parts accept liability for work performed by anyone attempting the repair or part replacement. These instructions are provided solely by Easy Spa Parts. Certain parts mentioned in the instructions are manufactured by third parties, including Dimension One Spas. Dimension One Spas has not supplied or reviewed these instructions. Dimension One Spas shall have no liability to you relating in any manner to these instructions or any acts or omissions by Easy Spa Parts