Spa Troubleshooting: Common Problems

How to treat the most common problems

One of the beauties of caring for a spa or hot tub is that when trouble occurs, it can often be readily remedied by Purging, Draining & Refilling. Why? Because we're dealing with a relatively small body of water. The most common problems are:

  • Foaming
  • Odors
  • Skin rashes


Foamy Spas & Hot Tubs

Excessive Foaming

Does your spa or hot tub look like this? We  hope not! Foaming is one of the most common spa water problems. Spa troubleshooting for foam is pretty simple.

Most times it's a matter of maintenance. Every once in a while it's just an innocent mistake. Then there's the standard prank! Of the 3 general causes, maintenance is the key reason for a foamy spa or hot tub. Let's face it, in time the spa is going to get foamy.  Why?

Basically, you're creating soap. To make soap you need 3 things: hot water, animal fat (read that as body oils & sweat), and high pH.  Your spa has all 3 happening most of the time! 

But first let's distinguish bubbles from foam. Bubbles are the normal air bubbles that come to the surface of the water & then burst. When  the jets are turned off, the bubbles dissipate within 10 - 20 seconds. Foaming  is just that - there's a "beer head" like foam sitting on top of the water when the jets are turned on. When the jets are turned off, it takes a while for the foam to dissipate.

Maintenance. Over time, body oils & perspiration, along with lotions, deodorant, body sprays, etc. build up in the water. The filter can only handle so much.  Remember, foaming means the water just gets OLD. Change it. At that point you will notice a gradual increase in the  bubble or foam build up. Instead of adding anti-foam and the water is old, change the water.

Poor water balance, especially high pH, will affect foaming. Water having a High pH (over 7.8) can also lead to stale & funky smells plus additional scaling. Water that's too soft can also contribute to foaming; adjust the water hardness to about 200 - 250 ppm.  

Those Innocent Mistakes - Mistakes do happen. Here's a quick list: using bath lotions or "bubble bath"; adding pool algaecide (in spas that are attached to pools, only use a non-foaming algaecide); deciding to bathe with soap in the spa; washing your hair in the spa (hey, you can't make this up); using household detergents for cleaning & maintaining the spa. All of these will cause foaming to one degree or another.

Pranks -  Every once in a while, there's a joker. But let's call it what it is: vandalism. And it's not funny. Causing a spa or hot tub to foam is relatively easy; just add detergent or soap. Depending on how much was  added, you may have to drain & refill the spa more than once.

An obviously very foamy spa that was vandalized... pranks are not cool!
An obviously very foamy spa that was vandalized... pranks are not cool!

Spa & Hot tub odors

Ooo that smell...

Does your spa or hot tub smell? Does it have odors that you just can't get rid of? Let's try to figure this out. More often than not, many spa owners blame the odors on "too much chlorine". Unfortunately, that is rarely the case especially if you're not using chlorine!  Some  odors are chemical, some are environmental. Most odors can be successfully treated and cured. Odors can even be prevented with proper maintenance.

Smelly Spa & Hot Tub Odors are caused by:

  • Improper sanitizer use
  • Improper water balance
  • Lack of  regular maintenance
  • Insufficient purge, drain & refill procedures
  • Environmental reasons caused by uncontrolled biofilm build up

Don't try masking odors with spa fragrances & aromatherapy products; you'll only make the situation worse. Deal with the root causes. After treating the odors, you will really enjoy the fragrances as they were meant.

Chlorine &  bromine are both excellent sanitizers used in spas and hot tubs.  When they are used, they do breakdown, they can combine with, waste products of what they have sanitized. These wastes are typically in the form of nitrogen & when the nitrogen combines with the chlorine, they become smelly chloramines; when combined with bromine, they become bromamines. The really bad news is that chloramines are virtually worthless at killing bacteria.  This is why it is necessary to shock the spa weekly, without fail!

After shocking, leave the spa cover off of the spa for at least 1  to  2 hours (ideally).  If the waste is not fully allowed to gas-off, the waste chloramines & bromamines literally hit the underside of the spa cover and fall back into the water! Even if your spa is not regularly used, it is an excellent idea to remove the cover for at least one hour weekly to let the bad air gas-off. 


Environmental reasons for spa & hot tub odors are due to the build-up of biofilms on spa surfaces and plumbing lines that contribute to the formation of White Water Mold and Pink Slime and all of their odors. As biofilms build, multiply, and spread throughout the spa system, odors worsen dramatically. For that reason it is almost mandatory to use plumbing line cleaning products such as Hot Tub Serum Total Cleanse or AquaFinesse SpaClean.

Your spa should smell clean
Your spa should smell clean

Skin rashes

Recreational Water Illnesses - Pseudomonas Aeruginosa

This  is a commonly occurring bacteria found in water and soil.  Pseudomonas Aeruginosa is listed as an "opportunistic bacteria" that can cause: Urinary Tract Infections, skin infections, lung infections (when it is aerosolized).

The rash that you see is NOT an "allergic reaction" to chlorine or bromine. It is true that some (and  we mean a very few) people may be hyper-sensitive to chlorine or bromine, but will normally not result in lasting symptoms as shown below. 

  • Dermatitis (Skin Rash or Pseudomonas Folliculitis)
  • Respiratory System Infections
  • Swimmer's Ear (Otitis Externa) - please see your local doctor for treatment
  • Other systemic infections

In Spas & Hot tubs, a very likely cause of skin rash is Pseudomonas aeruginosa (PA).  Pseudomonas feeds on oil & grease present in the spa water (mainly from body oils & skin treatments brought into the spa from  bathers NOT properly showering prior to entering the spa or hot tub and a very good reason to use ActivNzyme which can naturally breakdown those oils) and an multiply rapidly under ideal conditions (such as lack of proper  sanitizing procedures). 


For this reason, it is necessary to Purge, Drain &  Refill your spa on a regular basis, regardless of the condition or appearance of the water. Purging helps to remove most of the accumulated biofilms from the spa's surfaces where PA can hide & thrive. In swimming pools, PA can be found on various areas such as pool coping, waterfall edges, ladder steps, swim-outs, etc. 

PA infects the hair follicles on the body. 

If infected, you will notice the following characteristics of Pseudomonas Aeruginosa:    

  • Itchy rash 8 to 48 hours after contamination.
  • Rash can occur on arms, legs or trunk of body.
  • Rash disappears 7 to 10 days without treatment (ALWAYS check with your doctor).

Prevention: Enforce shower rules before entering spa or pool. Maintain 1-3 ppm Free Available chlorine in residual spas or pools and 3- 5 ppm in commercial spas  or pools.  

Why good chemical care & maintenance is so important... your health
Why good chemical care & maintenance is so important... your health

"hot tub lung"

Unhealthy odors...

"Hot Tub Lung" is a relatively new condition originally published in the "Mayo Clinic Proceedings" November 2002.  The condition is either an infection or an irritation due to exposure to mycobacterium avium complex (MAC) .

At temperatures above 84 degrees Fahrenheit, the level at which many if not most tubs operate, chlorine loses its much of its disinfectant properties, especially if proper sanitizing procedures are not followed, and MAC can flourish. The bubbles and steam rising from the spa or hot tub create an aerosol through which MAC readily enters the lungs by normal breathing or inhalation.  It should be noted that it is currently unclear from the reports whether this condition is an infection or hypersensitivity pneumonitis.

The Mayo Clinic researchers also noted that all of the reported cases of "hot tub lung" have been associated with INDOOR spas or hot tubs at a personal residence.

The condition is most likely to occur when spa & hot tub owners DO NOT physically clean the tubs (Purge, Drain, Clean, Rinse, Refill), chemically clean or change the filter(s) (use SpaGuard® Filter Cleaner) as often as is recommended and/or do not follow a proper sanitizing procedure.


Perform the following procedure to treat the infected spa or hot tub:

  1. Drain the spa and refill just above the jets.
  2. Remove the filter and soak in a solution of chlorine and water during treatment. (2 Tablespoons Dry chlorinating concentrate per 5 gallons of water)
  3. Shock with four times the normal dose of Stabilized Chlorinating Granules.
  4. Turn on the jets and circulate for 2 - 3 hours. The bacterial growth usually builds up in the lines, so it is necessary to flush them thoroughly. Use Hot Tub Serum Total Cleanse (best product in this case) to attack & remove the biofilm.
  5. Drain the spa again and refill with fresh water.
  6. Rinse & chemically clean and/or replace the filter.
  7. Re-balance the spa water (pH, total alkalinity & calcium hardness) and shock. Do not enter the spa until sanitizer level drops below 4.0 ppm.
  8. As an additional precaution, PoolSpaGuru STRONGLY RECOMMENDS cleaning the underside of the spa or hot tub insulating cover with a hard-surface disinfectant such as Pursue® Broad Spectrum Disinfectant Deodorizer or Lysol® following all label instructions for disinfecting.

Enforce shower rules before entering spa.
Maintain 1.0 - 3.0 ppm Free Available chlorine in residual spas and 3.0 - 5.0 ppm in commercial spas.

A side note:  Products such as Soft Soak® Sanitizer and Soft Swim® "B"  do not lose their effectiveness as water temperature increases.


chloramines in spas & hot tubs

Not "too much chlorine", but insufficient "working chlorine"...

Chloramines are one of the most common causes of water related problems in spas, hot tubs, and swimming pools.

Chloramines are often referred to as "combined-chlorines" because they are molecules formed by the combination  of chlorine in the form of Hypochlorous Acid (HOCl) and organic wastes (saliva, perspiration, urine) in the form nitrogen or ammonia.   Chloramines produce the "chlorine odor" that many people do not like (tear gas is a form of Chloramine). When people complain of "too much" chlorine, it is almost always the case of combined chlorine or chloramines causing the foul odor as opposed to a proper level of Free  Available Chlorine (FAC).  

But foul chlorine odors are just the ugly mask of the underlying problems present in Spas, Hot tubs & Swimming pool water.

Chloramines are the root of many  problems in pool water.  Chloramines cause problems because of their stability and persistence.  This stability and persistence forms additional Chloramines.  This is chlorine demand (consumption) at its  finest.  (Consumers complain that they "just shocked" the pool but  there's no chlorine showing when tested.) As more chlorine is added  without reaching break-point, more chloramines are formed thereby exacerbating the problem leading to what I'll call "obvious  problems" such as cloudy water or algae growth.  Homeowners and/or pool dealers unfamiliar with chloramines and chlorine demand begin  treating the symptoms (cloudy water or algae) rather than dealing with the root cause especially after the second or third treatment.   Without the knowledge of chloramines & chlorine demand, consumers  may not receive the help they need. 

We describe the problem this way  to our customers in regards to reaching break-point or satisfying  chlorine demand:  Reaching break-point chlorination is an "all or  nothing" proposition. Think of it as trying to jump the Grand Canyon  in a single bound; you can't "come close".  You MUST reach the  other side FIRMLY.  You can't "almost make it".  Whether you're 2  inches short or 100 feet short, you're still short.  


This is where our constant reminding of consumers of the need to weekly "shock" their chlorine or bromine spa.  Weekly shocking during the entire time the pool is open & operating will greatly reduce the potential of chlorine demand or consumption. 

Another facet to the chlorine demand and chloramines problem is the misconception that the spa or hot tub  "smells of chlorine", therefore (in the novice's mind) "I've got too much chlorine or too many chemicals present in the water" and  they stop adding anything to the pool, effectively ignoring the  problem. Testing goes out the window; pH and overall water balance go out of balance.  The spa owner is not convinced that their true problem is a "lack" of chlorine and particularly FAC.  This is especially  true if the homeowner or operator is using OTO (orthotolodine will  produce results for Total Chlorine only, using yellow color standards,  not differentiating the difference between FAC and chloramines present) for chlorine testing as opposed to the more accurate DPD (using pink  color standards) method (uses separate tests for Free Chlorine as well as Total Chlorine). 

Controlling small amounts (under  2.0 ppm) of chloramines is relatively easy.  Shock the spa or hot tub with a  good-quality granular chlorine or use an oxidizing compound containing  potassium mono-persulfate.  Mono-persulfate "shocks" are great  because they don't add additional chlorine that may contribute to  further Chloramine formation.  We have found that even when there are  larger amounts of chloramines present, the mono-persulfate works well in  reducing the chloramines by oxidizing these wastes and releasing the  combined chlorines.  Breakpoint chlorination often-times becomes simpler  to achieve.  Again, weekly shocking of the pool is the preferred preventative procedure.  Just because the pool water looks good doesn't mean that everything is balanced and working properly. 

A lurking problem? 

Another potential area or source of the Chloramine problem may be something we as dealers or is the fill or tap water itself. Almost all municipalities around the USA use chloramines instead of chlorine to treat the drinking water. There's nothing any one of can do about that. However, knowing & understanding this will help us to avoid the build-up of chloramines.

Again, the good thing about a spa or hot tub is that if the chloramine problem is too bad or out of control, it can be readily drained. Refer to our Purge, Drain & Refill instructions.