Troubleshooting Hot Tub Water Problems

This table should help you identify and correct most common water problems.

If you can't resolve your particular problem using this guide then you can always contact us for advice.

ProblemPossible CauseSolution
Cloudy Water

Old or dirty filters. This is the most common cause of cloudy water!

Thoroughly clean your filters using a powdered filter cleaner. A powdered filter cleaner will effectively remove scale, unlike liquid filter cleaners which are really just de-greasers. Powder filter cleaners can be used in a dishwasher if you wish.

If the filters are over a year old consider that they might need replacing.  It is always best to keep two sets of filters and rotate them so that you can allow each set to dry out thoroughly between cleanings. This allows the micro-fibre pores to shrink back to their original size enabling the filter to perform better and last longer.

Organic contaminants introduced by bathers (make-up, perspiration, urine, body oil); from swimwear (soap or fabric conditioner); food; drink etc.

You should use a shock treatment regularly to remove non-filterable wastes. Powdered, chlorine-based shock treatments are very effective and most also contains water clarifiers. A chlorine-based shock may leave a very low chlorine residual in your spa water for a few hours after treatment, so if you would like a completely chlorine free option try a non-chlorine shock, although be aware that it may be slightly less effective.

Excessively low level of sanitizer.

Santizer can be used up much more quickly than expected if unseen contaminants are introduced into the tub, such as from urine or if there is an excessive build-up of boifilm in the pipework. Check and adjust the santizer level and monitor regularly until the problem subsides.

High Total Alkalinity, High pH or Total Hardness is out of Balance causing scale formation.

Test water and adjust the water balance as necessary.

Build-up of unfilterable small particles, possibly caused by scale formation.

Use a water clarifier to coagulate the particles so that they can be removed by the filter. Ensure that the filter(s) are cleaned thoroughly and regularly with a powdered filter cleaner.

Aquafinesse

When using Aquafinesse it is common in the first 7 - 14 days after a water change to get very cloudy water. The only remedy to this problem is to clean the filters frequently (as often as daily) until the problem is resolved.

Excessive Foaming

Build-up of body oils, cosmetics and detergents from bathers or the use if inappropriate cleaning products

Use a shock to remove the organic contaminants (preferably a chlorine-based, powdered shock) and, if necessary, a good quality anti-foam to reduce the foaming. 

Try to use as little anti-foam as possible because it will always dull the water and increase the need for frequent water changes.  More importantly, avoid the problem by ensuring that no-one uses the hot tub whilst wearing makeup or body oils and lotions. Only ever use specialist hot tub cleaning products, never use household cleaners.

Total Hardness is too low

Test the Total Hardness level and use a hardness increaser to increase the level to at least 250ppm.

Large amounts of dissolved solids (contaminants) in the water.

It can't be avoided.  the longer the water is in your tub, the more dissolved solids will build up until the problem gets too bad and you just have to change the water!

Chalky, White Scale Deposits

High Mineral Content in Water

Consider using a pre-filter on the hose when you fill the tub to reduce the mineral content of the water as much as possible. If the problem stll persists then use a 'Scale Away' product on a regular basis.  It won't get rid of the scale but it will stop the scale precipitating out of the water and depositing itself into the tub or filters.

High Total Alkalinity, pH or Total Hardness.

Probably all three! Test the water and adjust the water balance as necessary

Cloudy Green Water

Algae

Try using a chlorine-based shock product to kill the algae. Then check, adjust and maintain a sufficiently high santizer level. If the problem is severe the only sensible option may be to drain the tub and re-fill with clean water.

Clear Green Water

Aquafinesse

The sanitizer Aquafinesse can often cause a green tinge to the water which is particularly obvious if you have a light coloured tub. This is a 'feature' of the product.

Over-dose of PristineBlue or other copper-based sanitizer

The concentration of PristineBlue will diminish over time. If the problem is severe consider part draining and topping up with fresh tap water.

Dissolved copper in the source water

This would would be an unusual occurrence in the UK, but if necessary a 'Scale Away' product may be used to sequester the minerals from the water.

Brown Water

High iron or manganese content in the source water

Consider using a pre-filter to reduce the mineral content as much as possible before it enters your tub. If the problem still persists then use a 'Scale Away' product to sequester the minerals from the water.

Odour

Excessive organic contaminants introduced by bathers (make-up, perspiration, urine, body oil); from swimwear (soap or fabric conditioner); food; drink etc.

Use a shock to remove the non-filterable wastes (see avove).

Thoroughly clean your filters.

Check, adjust and maintain sanitizer level.

Chloramines - the chlorine smell!

Chloramines are a bi-product of chlorine reacting with bacteria.  The only way to remove them from the water is to drain and re-fill.  Consider changing to a low chlorine or chlorine-free sanitizer such as ecoONE.

Eye / Skin Irritation

Total alkalinity or pH out of balance.

Test the water and adjust the water balance as necessary.

Excessive organic contaminants introduced by bathers (make-up, perspiration, urine, body oil); from swimwear (soap or fabric conditioner); food; drink etc.

Use a shock product to remove the non-filterable wastes.

Chloramines from chlorine-based sanitizer.

Chloramines are a bi-product of chlorine reacting with bacteria.  The only way to remove them from the water is to drain and re-fill.  Consider changing to a low chlorine or chlorine-free sanitizer such as ecoONE.

Scum Deposit at Waterline

Oils, lotions and detergents from bathers and costumes or the use of incompatible cleaning products.

Clean the waterline using a specialist hot tub surface cleaner, not a household product which will cause foaming. Use a shock product to remove as much of the contaminant as possible. 

If the situation persists the only solution is to perform a complete water change.

Inability to reduce the pH

The Total Alkalinity is too high.

Reduce the Total Alkalinity before you try to adjust the pH. Adjust the Total Alkalinity to within the recommended range for your sanitizer using a TA Reducer.

Wide pH Fluctuations

Total Alkalinity too low

Increase the Total Alkalinity to within the recommended range for your sanitizer using a TA Increaser.