Best Hot Tub Chemicals Frequently Asked Questions

Can Spa Marvel be used in a hot tub without chemicals?

Although sanitizer should be used as per local regulatory requirements, it is possible to reduce sanitizer use even further by using the best hot tub chemicals, which are available from your professional spa retailer, and by following the instructions on the Tips for Reducing Chemical Use section.

How do we know Spa Marvel is working?

Spa Marvel will allow you to maintain your desired sanitizer levels while using less sanitizer, moisturize skin, help to maintain pH and alkalinity, and prevent foaming and scum lines.

Is Spa Marvel compatible with other spa water treatment products?

Spa Marvel works in all makes and models of spas, and is compatible with all other water treatment systems including chlorine, bromine, salt water, biguanide products, ionization, ozone and ultra violet. Whether you are trying to get as close as you possibly can to having a hot tub without chemicals, or whether you are following a more traditional spa-water treatment regimen, Spa Marvel is a great choice to complement your water care program.

How does Spa Marvel compare in price to using traditional spa treatment products?

The cost of using Spa Marvel will be offset by savings realized through reduced chemical cost and reduced wear and tear on equipment, heaters, lids, and bathing suits.

Does the Spa Marvel Cleanser need to go into hot water, or will cold water work?

The same way it is easier to wash grease and butter from your hands in warmer water, Spa Marvel Cleanser will perform better in warmer water than in colder water.

Is it okay to use hard or soft water with Spa Marvel?

Spa Marvel will work with water of all hardness levels. We recommend that you balance your water hardness as per your professional spa retailer’s recommendations. Be sure to use the best hot tub chemicals which are available from your professional spa retailer as opposed to chemicals found at big box stores that are often of a lesser quality.

How long does Spa Marvel last for?

Spa Marvel has a 10 year shelf life. One full bottle of Spa Marvel will treat any tub up to 500 gallons (2000 liters) and will last 3 months with regular use. Spa Marvel is engineered to account for the fact that tubs do experience some degree of spillage through regular use. Keep in mind that if you lost most of your hot tub water (i.e. a major leak or massive spillage) that Spa Marvel may not last as long as 3 months. Every 3 months simply add another bottle of Spa Marvel. In a swim spa, use 1 bottle of Spa Marvel per month.

How often do I need to change my water when using Spa Marvel?

Change your water as per your professional spa retailer’s guidelines, or when your Total Dissolved Solids (which your retailer can measure for you) approach 2,000 ppm, and do not go past 1 year without changing. It is, however, good practice to change water every 3 months. Use Spa Marvel Cleanser prior to changing the water. However, even when using the best hot tub chemicals, it is a good practice to change the water every 3 months. Use Spa Marvel Cleanser prior to changing the water.

My tub is only 250 gallons (1,000 litres), do I only use ½ of the bottle of Spa Marvel every 3 months?

Every time you get out of the spa, you take some Spa Marvel out with you. It is for this reason that you need to add more very three months, and you should add 1 full bottle of Spa Marvel for all tubs up to 500 gallons, regardless of size.

What happens if I go more than 3 months without adding another bottle of Spa Marvel?

You will need to use more sanitizer to maintain desired readings, pH and alkalinity may begin to wander, the soft-skin feeling will diminish and you may begin to encounter foaming and scum lines. It is important to replenish Spa Marvel every three months, especially if you are trying to get as close as you can to having a hot tub without chemicals.

Can we use Spa Marvel in a swim spa or pool?

One bottle of Spa Marvel treats up to 500 gallons (2000 liters) for 3 months with regular use. In a swim spa add 1 bottle of Spa Marvel per month. In a swimming pool, use Pool Marvel. Do not use Pool Marvel in a swim spa or hot tub as it will cause excessive foaming.

Can Spa Marvel be apportioned for shorter periods of time?

Yes. If for example your tub was at a vacation home that you used only 2 months of the year, you can use 2/3 of the bottle of Spa Marvel for 2 months. This formula can also be used if you are planning extremely heavy use of your spa. i.e. if you know that you are having a party a month after filling the spa that will result in such heavy use that a water change will be necessary, use 1/3 of a bottle of Spa Marvel to last for that month. After the party, change the water and use the remaining 2/3 to last another 2 months.

Is Spa Marvel Water Treatment and Conditioner safe?

Yes. Spa Marvel is safe for children, pets, and birds and does not stain clothes, ruin highlights in hair or harm jewelry or nail polish. Spa Marvel is a product so safe that it does not require warning labels or child resistant packaging, making it one of the safest hot tub chemicals on the market. Spa owners seeking the safest hot tub chemicals swear by Spa Marvel in part because it is an all natural enzyme-based product.

What are the safest hot tub chemicals?

All chemicals can pose some risk whether to bathers themselves or the hot tub and its equipment. So the safest hot tub chemicals depend on a couple of factors. First, what, if any, health conditions you may have or are prone to. And second, whether you’re looking for the safest hot tub chemicals for the life of your spa equipment.

Some chemicals, however, are more harsh or harmful than others. Chlorine can be particularly hazardous and therefore, should be used carefully and properly. One of the hazards is chlorine poisoning. This can be triggered by either swallowing it or inhaling its fumes. Chlorine can cause burning and discomfort of the eyes and nose, burning in the throat, difficulty breathing, nausea and vomiting, skin redness, and chest pain. That’s why handling chlorine carefully and properly testing the chlorine levels in your hot tub is necessary.

When looking for the best or safest hot tub chemicals, those sold at big box stores are often of a lesser quality. So choose the best hot tub chemicals that are available from your professional spa retailer.

Hot tub owners seeking the safest hot tub chemicals often choose Spa Marvel. It is an all natural enzyme based product available from many professional spa retailers. It is the preferred choice for those looking for the safest hot tub chemicals for sensitive skin.

For further details on the safest hot tub chemicals, or options for a hot tub without chemicals, read the above FAQ titled ‘What are the best hot tub chemicals for sensitive skin?’

Why do we need to use Spa Marvel Cleanser prior to using Spa Marvel, especially if our hot tub is new and never been used?

The plumbing system of a hot tub will accumulate buildup over time from chemical binders, body oil, soap residue, calcium, minerals, and more. The reason that we recommend the use of the Cleanser first is that Spa Marvel Water Treatment has inherent descaling properties. When added to water in a hot tub, the Spa Marvel itself will clean the accumulated debris out of the plumbing and as this debris is introduced to the water it may cause cloudy water, odours, fluctuations in pH and foaming. It is for this reason that we recommend using the Cleanser in the old water prior to draining as the Cleanser will remove this buildup prior to the fresh fill.

In a brand new spa the plumbing is coated with wax, silicone, lubricants, sawdust, etc. leftover from the manufacturing process. When Spa Marvel Water Treatment is added to water in a new spa, it cleans those residues from the plumbing, and the resulting debris can impair water quality once Spa Marvel cleans it out.

Ideally in a new spa, the Cleanser should be used to remove residue from the manufacturing process before the spa is put into use. If you forego this you may encounter poor water quality and will need to shock the water to clear it up.

Can you use lake water with Spa Marvel?

Yes. If the lake water is cloudy due to tannins in the water, you will need to use spa shock and/or a clarifier to help in clearing it during the first few days.

Where should my pH and alkalinity be?

Alkalinity should be between 80ppm and 150ppm or as directed by your professional spa retailer. The spa industry traditionally recommends that pH be between 7.2 and 7.8. However, Spa Marvel reduces the surface tension of the water, and when surface tension is reduced the acceptable pH range increases to between 7.2 and 8.2. As long as your pH is between 7.2 and 8.2 when using Spa Marvel, leave it alone, it will not be detrimental in any way to you or to your spa.

What are the best hot tub chemicals for sensitive skin?

If you have sensitive skin, such as psoriasis, you’ll want to take special precautions when treating your hot tub water. Generally, the safest hot tub chemicals for sensitive skin are treatment systems and products that result in a reduction of harsher chemicals required to maintain appropriate sanitizer levels. These options include:

Biguanides
Ozonators
Ionizers
Ultraviolet purifiers
Saltwater generators
Spa Marvel Water Treatment and Conditioner

Biguanides, also known as polyhexamethylene biguanide (PHMP), are a non-chlorine and non-bromine sanitizer. When it comes to adding sanitizer chemicals, these are among the safest hot tub chemicals for sensitive skin.

Although it’s a more gentle option than traditional chlorine and bromine chemical sanitizers, it does have its drawbacks. First, biguanide doesn’t destroy organic material. So adding hydrogen peroxide will become a regular part of your hot tub water maintenance. Biguanide also causes foaming. This poses a problem because to sanitize hot tub water properly, the foam must be entirely removed daily, at a minimum. Third, after a few years of use, microorganisms develop immunity to biguanides. This results in mold and slime.

Ozonators reduce chemical use by creating ozone to help destroy bacteria and oxidization of other contaminants, such as body lotion, saliva, and makeup. Many hot tub owners wanting to use their hot tub without chemicals use ozonation but are still required to use sanitizer. Although ozonator systems do not allow for a hot tub without chemicals, they can reduce the time and cost to maintain your spa.

The cons are that ozone is corrosive and hyperactive ozone systems can produce excessive ozone gasses that can damage hot tubs. So when looking for the safest hot tub chemicals, there may be better alternatives.

Ionizers purify water by releasing copper, silver, or zinc ions into the water through electrolysis. If you’re looking for the safest hot tub chemicals, ionizers can dramatically reduce the use of harsh chemicals. Still, you won’t completely be able to run your hot tub without chemicals. Although ionizers are excellent at fighting algae and bacteria, they aren’t effective at breaking down lotions, bodily fluids, and many other contaminants. Another con is that it requires monitoring of the hot tub water’s metal concentration and maintaining appropriate metal levels. Otherwise, excess metal concentration can result in staining on the surface of the tub over time.

Ultraviolet water purifiers In addition to using the best hot tub chemicals you can, you may also want to consider an ultraviolet water purifier, which can destroy up to 99.99% of microorganisms, without the use or production of additional chemicals. These systems are also easy to maintain once installed. They typically require only annual bulb changes and periodic changing of the protective lamp filter.

The cost of these systems, however, will set you back several hundred dollars. But they can pay for themselves over the long term by reducing spa maintenance costs associated with traditional treatments. However, you still will not be able to run your hot tub without chemicals because UV systems do not remove non-organic contaminants such as lotions, chlorine, and heavy metals . Also, if you use lake or well water that isn’t clear, it may cause floaties or murky water. This is easily remedied, however, by using a pre-filter such as Spa Marvel’s X10 Water Filter.

Saltwater chlorine generators are another mechanism that can allow you to operate your spa with fewer of harsh chemicals. Contrary to what many people think, salt water spas are not chemical free hot tubs because they actually produce chlorine. Still, a saltwater spa may provide a more soothing experience than that of many traditional hot tub water treatments. This can be particularly beneficial for those looking for the best hot tub chemicals for sensitive skin.

At the same time, the chlorine in these systems is sometimes known to cause rashes, burn eyes, and bleach bathing suits. The initial cost of a saltwater system can range between $500 to $5,000. Also note that salt is corrosive, so it can damage underwater lighting, heaters, and other metal components.

Regardless of the system you use, to ensure great water quality, be sure to use the best hot tub chemicals which are available from your professional spa retailer.

Can I use my hot tub without chemicals?

Using a hot tub without chemicals is not recommended. Using Spa Marvel will allow you to significantly reduce the chemicals used in your spa. Other alternatives are discussed in the above FAQ, ‘What are the best hot tub chemicals for sensitive skin?’

Spa Marvel Water Treatment and Conditioner is compatible with all spa water treatment products, and can reduce and eliminate many of the chemicals used in traditional hot tub water care, eliminating problems such as scum lines, hot tub rash, scale buildup, foaming and dry skin. Spa Marvel is an all-natural treatment that’s so gentle on hair and skin, that you won’t feel the need to shower after using your tub.

Spa Marvel is one of the safest hot tub chemicals for sensitive skin, in part due to its inherent skin conditioning properties, and in part due to its ability to reduce the amount of harsh chemicals used in your spa.

Water Quality Questions

Spa Marvel users should expect to enjoy clear, odour free water at all times. On very rare occasions some users have occasionally experienced less than perfect water and have sought assistance. Below are answers to these infrequently asked questions:

Foamy Hot Tub Water

Spa Marvel reduces surface tension of the water, which removes the platform necessary for detergent-based foaming to occur. Foaming caused by detergents typically doesn’t happen in Spa Marvel tubs. Persistent foaming in a Spa Marvel tub is usually caused by one of four things:

Low pH and/or alkalinity.
Water that is too soft.
Dirty filters. Even a single bather who may have introduced some type of contaminant, like a body lotion/cream etc. can foul a filter, resulting in foaming.
Certain filter cleaning products can cause foaming if the filter cleaner is not rinsed thoroughly from the filter. Spa Marvel Filter Cleaner does not cause foaming. Always ensure that filter cleaning agents are thoroughly rinsed from the filter pleats after cleaning.

Film on Spa Walls

Spa Marvel contains positively charged ions and your spa surface has a negative charge. Occasionally a bond between these two charges will occur resulting in a slight film that may develop on the spa walls. Simply wipe the surface with your hand or a cloth (rinsed well to remove any existing detergents) to break this bond. The bonding also creates a natural lubricant that allows your spa’s mechanical components and heaters to work better.

Musty Odour in hot tub

Musty odours are typically a result of contaminants that have accumulated in the spa’s filters or are caused by musty water that drips from the spa cover back into the tub.

Properly clean filters using a product such as Spa Marvel Filter Cleaner, and clean the spa cover. If odour persists, shock the water.

Seaweed/Pond Odour

Caused by the development of algae in the spa. Shock the water with 30 grams (2 tablespoons) of sanitizer per 1000 litres (250 gallons) of spa water.

Cloudy or Discoloured Spa Water

If these conditions occur within the first week of using Spa Marvel it is typically a case of the Spa Marvel Cleanser having not been able to completely remove all contaminants from the plumbing of the spa. Spa Marvel Water Treatment & Conditioner will, over a period of time, loosen these contaminants causing them to be released into the spa water. You will now experience stronger jets, quieter pumps and more efficient heating elements, but as the contaminants are released into the spa water you may experience a combination of cloudy or discoloured water, major changes in pH, foam and odours. In brand new spas these conditions may occur as the spa off-gasses and Spa Marvel removes other contaminants leftover from the manufacturing process.

High pH and/or high alkalinity can also cause cloudy water.

If these conditions occur after the first week of the introduction of Spa Marvel it is typically a result of low filtration times and/or dirty filters. Ensure that your filter is properly cleaned and that the spa is scheduled to filter a minimum of 6 hours per day.

To correct these conditions:

PROPERLY clean filters with a product such as Spa Marvel Filter Cleaner.
Shock the spa water.
Add a water clarifier.
Increase sanitizer level.
Check alkalinity (80 – 150 or as directed by your professional spa retailer), and pH (7.2 – 8.2) and adjust if necessary by using traditional spa-water balancing products To ensure great water quality, be sure to use the best hot tub chemicals, which are available from your professional spa retailer. The acceptable range for pH when using Spa Marvel is much broader than when using traditional spa care products, so please take care to read your testing devices properly.
Allow the tub to circulate/filter continuously (or as much as it can) for 24 hours for these steps to work, then re-clean the filter.

If after 24 hours the water is still not perfect, repeat the above steps. If after repeating these steps you are STILL experiencing difficulty, please contact our Solutions Department for further assistance.

Solutions Department: info@spamarvel.com or call 1-888-400-1772

Greenish/Yellowish/Brownish Tint in hot tub

Tinges of colour occur when minerals in the source water oxidize (rust). It won’t hurt you, it just looks bad.

To correct this, shock the water with 30 grams (1 ounce) of chlorine or bromine per 1000 litres (250 gallons) of water. Twenty four hours later if the water is not clear, check the chlorine/bromine reading. If the reading is below 3 ppm, shock it again. If it is above 3 ppm, wait another 24 hours and check again. Multiple treatments may be necessary.

Flakes in the hot tub water

Flakes that are in your spa resembling pieces of skin, or may be akin to pieces of tissue paper in the water are indicative of white mould in your plumbing.

White mould is an airborne spore that comes from trees, and develops in areas left damp such as garden hoses, dehumidifiers, sump holes, children’s bathtub toys, hot tub filters that are left outside and reinstalled while not completely dry, swimming pools and hot tubs.

White mould can be introduced to spa plumbing from wet testing at the time of manufacturing, or in the time between when it was drained at the showroom till the time it gets to your house. It can occur if you drain your tub and don’t refill it for a few days. White mould can also be introduced to spa water when filled from a garden hose that has developed some white mould while lying out in the sun and sometimes it just drifts into your spa water while the lid is open.

White mould can even remain in your tub and be kept at bay for months and years by conventional sanitizers such as bromine and chlorine. If you go an extended period of time without adding chlorine, the white mould can proliferate to a point that it becomes apparent (often 6-8 weeks before you notice it). Left unattended white mould can overwhelm your spa.

One of the best hot tub chemicals to kill white mould is granular chlorine, which is used to super-chlorinate the water. Remove any headrests and leave the lid open for at least the first hour while performing this treatment. Add 2.5 ounces (5 tablespoons, 75 grams) of chlorine per every 100 gallons (400 litres) of spa water or part there of.

For this treatment to be effective it is imperative that the chlorinated water is distributed throughout the entire plumbing system. Ensure that all jets, valves, waterfalls, water features, aerators and diverters are open and are subjected to the chlorine. If your tub has a drain next to the pump or at the base of the cabinet to which you can attach a hose to facilitate draining, ensure that some of the chlorinated water is bled through the drain at the onset of this procedure. This is very important to do because any built in drains are a dead end in the plumbing and the chlorine will not naturally make its way down to that part of the plumbing, but the mould will.

Check the chlorine reading after 24, 48 and 72 hours. If at any of these intervals the chlorine is anything less than ridiculously high (20ppm), treat the tub again with chlorine and start the clock over on the 72 hour time period.

Do not use the spa during this process.

It is important to note that the chlorine will kill the white mould so that it doesn’t continue to grow, but it will not make the flakes vanish.

After 72 hours of successful chlorination:

Remove your filter and clean it. Properly cleaned filters are pivotal to successful spa water care.
Using a filter soak such as Spa Marvel Filter Cleaner is recommended. After soaking the filter in filter cleaner it is critical that the debris is thoroughly removed from the pleats of the filter. The water pressure from showers, dishwashers and kitchen sinks is often not strong enough to remove the debris. If after rinsing your filter there is still discolouration in the pleats or if it still smells dirty, then it is not clean and you need to reevaluate your current filter cleaning techniques. Many people use a pressure washer (gently and carefully) to quickly and effectively remove the debris after soaking the filter. If you do not have access to a pressure washer, the sprayer at the coin-operated car wash works well. Most reusable hot tub filters ought to be replaced after 6 months of use.
Add the bottle of Cleanser (small green bottle) to the tub and run the jets on high-speed for 1 hour. Longer is fine, but for what we are doing 1 hour will suffice.
Drain the spa.
Rinse everything out, run a little fresh water through the filter well, and through each jet for a few seconds. Do your best to remove all of the old water.
Install the clean filter and refill the tub. When a tub is drained there are still several gallons of water that are in the plumbing, and this water can contain leftover flakes of white mould. When you fill the spa, turn all of the jets on and if you see a lot of the flakes come out of the plumbing, drain and fill the spa again. If there are only a few flakes your filter will pick them up or they can be manually removed.
Carry on as before.

Salt-Like Crystals on the Spa Walls

This condition is caused by alkalinity and/or pH being too high, which allows calcium to precipitate from the water and attach to the spa walls, leaving a rough, unpleasant surface. To correct this, balance alkalinity (80 – 150 or as directed by your professional spa retailer) and then pH (7.2-8.2) by using traditional spa-water balancing products available from your professional spa retailer. The acceptable range for pH when using Spa Marvel is much broader than when using traditional spa care products, so please take care to read your testing devices properly.

Manually scrub the buildup from the spa walls, being certain not to use anything abrasive. pH and alkalinity adjusting products are amongst the safest hot tub chemicals that you may use, and are much safer than having unbalanced water in your spa, which could damage equipment and affect bather comfort. See your professional spa retailer for a scrubber designed to safely clean the surface of your spa walls, or at a minimum do not use anything that you wouldn’t use on a Teflon frying pan or on the paint of your car. Once the crystals are removed they will go back into solution.

There are several reasons as to why your alkalinity or pH were too high and caused this:

The source water was not balanced on the initial fill.
Due to evaporation or spillage, you have recently added large amounts of un-balanced water to the existing spa water, which raised the alkalinity and/or pH.
There was still debris in the plumbing of your spa that was not removed during the cleansing process. As Spa Marvel reintroduces the debris to the spa water it can cause fluctuations in pH and alkalinity.
Your tub is not filtering/circulating often enough. Spa Marvel works best at a minimum 6 hours a day of circulation/filtration, and if it is getting less than that it may cause the water to go out of equilibrium and then the ph and alkalinity will not be properly maintained.