Water Treatment Troubleshooter for solving your pool water problems
 
Symptom
Possible Cause
Possible Reason
Solution
Chemical
Cloudy Water
Build up of dirt & bather pollution.
Insufficient chlorine or poor filtration
Backwash filter then super chlorinate. Add
clarifier to polish water.

Liquid Chlorine
Sparkle

Start of algae growth
Insufficient levels of chlorine.
Super chlorinate. After 24 hours Liquid Chlorine
backwash filter. Maintain chlorine level above 3ppm. Prevent recurrence of algae growth.
Liquid Chlorine
Chlorine Granule
Chlorine Tablets
Algaecide
Chlorine ineffective
Over stabilization
Dilute pool water and super chlorinate.
Liquid Chlorine
Ineffective filtration
Filter blocked or filter media needs renewing
Check sand, filter cartridge or D.E. Media
See below
Suspended particles
Precipitation of salts due to high PH or high alkalinity.
Correct pH and/or alkalinity
Dry acid
Unpleasant Water
High combined chlorines.
Free chlorine levels too low
Dilute pool water
Sore eyes/throat.
Itching Skin
Detergents from cleaning compounds getting into pool water.
Reaction between chlorine
and detergent.
Use chlorine compatible cleaners.
Tile & liner cleaner
Water too acidic or alkaline.
pH too low or too high.
Correct pH as in chart.
Dry Alkali or Dry Acid
Chlorine level difficult to maintain
Sunlight destroys chlorine.
Chlorine not stabilized.
Use stabilizer or stabilized chlorine.
Stabilizer. Chlorine granules or Chlorine tablets.
Build up of pollutants
Insufficient chlorination.
Super chlorinate
Liquid Chlorine
High water temperature
Organisms multiply more rapidly.
Increase dose rate of sanitiser.
Chlorine granules or chlorine tablets.
Apparent inability to get a chlorine reading on test kit in spite of chlorine addition.
Chlorine levels may be too high
High chlorine content bleaches reagent in test tablet
Dechlorinate. Allow chlorine to reduce naturally over a period of time. If very high reduce with chemicals.
Neutraliser
pH too low
Low pH of local mains water
Insufficient Dry Alkali being added.
Add Dry Alkali as per instructions. pH to be between 7.2 & 7.6.
Dry Alkali
Use of acidic chlorine donors.
pH too high
High pH of local mains water
Insufficient Dry Acid being added, or applied incorrectly
Add acid as per instructions .Maintain pH to be between . 7.2 & 7.6.
Dry Acid
Use of alkaline donors.
High alkalinity
Reduce alkalinity to 200ppm Check pH
Dry Acid
Salts being leached from new concrete pools
Self correcting over a period of time
Add acid to maintain pH between 7.2 & 7.6.
Dry Acid
pH levels erratic
Insufficient bicarbonate to buffer pH.
Low total alkalinity.
Add bicarbonate. Min 100ppm required.
Alkalinity Increaser
pH locked
Too high a level of bicarbonates.
Topping up from the mains water can increase alkalinity in hard water areas.
Reduce alkalinity to 200ppm Check pH.
Dry Acid
Low Alkalinity
Bicarbonates reduced by dilution particularly in soft water areas.
Mains water has low level of bicarbonates.
Add bicarbonate. Min 100ppm required.
Alkalinity Increaser
Pool walls feel slimy
Algae growing
Insufficient chlorination and pool wall brushing.
Super chlorinate to kill algae. Sweep or vacuum debris. Prevent recurrence with algaecide.
Liquid Chlorine
Algaecide
Dirt on pool wall at water line.
Build up of body fat, sun oil or cosmetics.
Irregular cleaning of surfaces.
Clean with environment friendly chemical.
Tile & Liner Cleaner
Rough scale formed on pool surfaces.
Water out of balance
Ratio of calcium hardness to total alkalinity incorrect
Check levels of pH, alkalinity and calcium. Seek advice from us.
Go to 'Contact Us Page'
Sharp edges round tiles.
Grout being leached by water.
Mains water too soft.
Regrout the pool. Increase calcium levels to min. 250ppm & maintain. Consider changing sanitiser to HTH Calcium Hypochlorite which will ensure calcium levels are maintained.

HTH

Calcium Hypochlorit

Ineffective Filtration
Sand filter
Is the sand level correct?
no:
No Not enough sand to filter out particles.
Renew or top up sand.
Go to 'Contact Us Page'
yes:
Blocked filter or filtration needs assistance
Backwash filter and use filter aid.
Sparkle
Cartridge filter:
Is cartridge in good clean
condition?
no:
Filter allowing particles to pass through.
Renew cartridge
Go to 'Contact Us Page'
yes:
Filter requires assistance
Backwash and use filter aid.
Sparkle
Pool left unattended for long period of time
Unable to treat daily.
Use Fi-Buoy. Remember to run filter daily on a timeclock.
Fi-Buoy
pH Scale on test kit


Symptom : Tinted or blonde hair turns a green colour after swimming.

Diagnosis
Levels of copper in the pool are too high. It may be that the water is too acidic (low pH) and that this is corroding the fittings of the heater. Alternatively you may be over-using algicides that are copper-based.
Cure
Your local pharmacist should be able to recommend a shampoo to restore the hair's original colour
Prevention
Use copper-based algicides more sparingly. Raise the pH of the water using soda ash.

 

 
 

Problems with the water in your pool, spa or hot tub can cause a host of effects. Please check your water regularly.

Swimming Pool Problems
It is very difficult to make one definite diagnosis when faced with symptoms of swimming pool water problems. You should use other evidence when considering what to do (e.g. test results) and go with the one you think is most likely.

Symptom : Black Spots

Diagnosis
These are caused by black algae.
Cure
Unfortunately, black algae is very tenacious and will require quite a bit of effort to remove. For minor problems, try persistant brushing combined with a good black algaecide. You will also need to clean the filter thoroughly. If the problem is more major, you may need to drain the pool and chlorine wash.

Symptom : Cloudy / Milky Discolouration

Diagnosis (1)
Dirt or bather pollution in water suggesting inadequate filtration
Cure (1)
Backwash the filter and raise free chlorine levels to around 10 parts per million using unstabilised chlorine. Polish water by adding a clarifier.
Diagnosis (2)
You are using stabilised chlorines and there is too much stabiliser in the water. This causes the chlorine to take longer to kill micro-organisms and so they build up and give a haziness to the water.
Cure (2)
Lower levels of stabiliser by replacing some of the water – either by performing an extra large backwash or by draining to waste. Then top up with fresh mains water. Superchlorinate by raising free chlorine levels to around 10ppm using unstabilised chlorine.
Diagnosis (3)
The filter is ineffective or has become blocked.
Cure (3)
Check the sand and replace if necessary (or get your dealer to do this.) If the sand particles have become coated in calcium (this happens mainly in hard water areas), the filter is not blocked and everything else seems fine, sharpen the sand with a filter cleanser.

Diagnosis (4)
Fine suspended particles in water that are formed as dissolved hardness salts transform to small solid particles by a process called precipitation. This is probably a result of a high pH or alkalinity.

Cure (4)
Lower the pH using dry acid until an adequate reading is obtained.

Symptom : Cloudy Green

Diagnosis
Algae is present in the water. This suggests that chlorine levels have dropped too low or it has become ineffective.
Cure
Shock dose with unstabilised chorine to kill the algae (10ppm for green tints, 25ppm if the bottom of the pool is not visible.) Brush off remaining algae on pool surface (including underwater lighting and step ladders.) Wait 24 hours. Backwash filter to clear out dead algae. Use water clarifier to remove haziness.
Prevention
Maintain chlorine levels at around 3 ppm. Use an algicide (or chlorine with added algicide) regularly if algae becomes a big problem.If you are using stabilised chlorine and testing indicates adequate levels of chlorine but you are still getting algae, see Diagnosis 2 above

Symptom : Rusty red coloured water

Diagnosis
Pipes or other steel/iron-containing fittings in the circulation system are being corroded by a high water acidity (low pH level.) The corroded particles are then oxidised by chlorine shock doses and this causes rust.
Cure
Act quickly to prevent the liner being stained and other damage. Contact your pool dealer / installer and see whether you can drain down and replace the water all at once or whether you need to use progressive dilution. Use a good liner and tile cleaner to remove any rust stains.
Prevention
Replace the offending metal fittings with PVC or copper. Ensure that the water has a pH and total alkalinity level within recommended limits.

Symptom : Sore throat, skin irritation and stinging eyes.

Diagnosis (1)
The pH level of the water is too high (alkaline) or too low (acidic).
Cure (1)
Aim for a pH of around 7.4. Use dry acid to lower the pH or soda ash to raise the pH.
Diagnosis (2)
High levels of combined chlorine (chloramines). An unpleasant “chlorine” smell tends to accompany this problem. Perform a DPD no3 test and check the results.
Cure (2)
Superchlorinate the pool (up to 10ppm free chlorine) in order to break down the chloramines.
Prevention (2)
Ensure that combined chlorine forms no more than 1/3 of the total chlorine in the pool.
Diagnosis (3)
You are using a detergent that is not chlorine compatible, for example to remove tide-marks or to clear pool sides. Some detergents react with the chlorine and these reactions can cause irritation to the skin and eyes. Traces of soaps and shampoos (from bathers) can cause similar reactions. Superchlorinate to ensure that all of the detergent(s) has/have reacted away.
Prevention (3)
Switch to cleaners that are compatible with chlorine or clean manually.
Diagnosis (4)
You are using the pool whilst sweaty or wearing makeup. Perspiration and cosmetics both contain nitrogenous compounds which react with free chlorine.
Prevention (4)
Have a thorough wash or shower before entering the pool.