Troubleshooting problems in swimming pools and spas




Recommended Products

Low chlorine levels.

Unsatisfied chlorine demand in the water at start up, after holidays or due to excess contamination or neglect.

Shock dose pool with liquid shock or granules (Sodium Hypochlorite or Calcium Hypochlorite) and retest after 24-hours. If chlorine level is still low repeat shock treatment.

Buy Shock Chemicals.

Too much chlorine.

Too much chlorine was added to pool.

This is only a real problem if the chlorine is over 10mg/l (ppm). The chlorine level will naturally dissipate in time or can be reduced by chlorine reducer.

Buy Chlorine Reducer.

Chlorine levels will not stabilise or are lost rapidly.

1) PH balance incorrect.
2) Chlorine stabiliser not present.

1) Balance pH to 7.2 to 7.6
2) Use stabilised chlorine granules (Sodium Dichloroisocyanurate Dihydarate)
3) In spas consider the use of Bromine tablets which are more tolerant of pH swings.

Buy Stabilised Chlorine.

pH hard to control.

pH levels can be difficult to control if the total alkalinity is incorrect.

Correct total alkalinity level.

Buy Balance Chemicals.

Green water.

Usually caused by an infestation of algae.

Shock dose pool with chlorine and add algaecide.

Buy Algaecide.

Cloudy water.

Usually occurs after poor chemical control or inadequate filtration.

Clean filter, check and if necessary adjust chemical levels (chlorine & pH). If problem persists use water clarifier to assist filter in removing small particles. (It is dangerous to operate a pool if the bottom is not visible).

Buy Clarifiers and Flocculents.

Scale Formation.

This can happen in hard water areas due to high level of calcium in the water.

Ensure the correct pH level is being maintained and use a Scale Inhibitor to prevent calcium precipitating out of the water.

Buy Scale Inhibitors.

No colour change on Test Strip pads after being dipped into pool water

1) If chlorine level is over 15mg/l (ppm) the colour on the pads can be 'bleached' out.
2) If chlorine level is low the test strip colour will not change for the chlorine test.

Check expiry date on Test Strips.
1) Wait for chlorine level to drop and retest.
2) Add chlorine.

Buy Test Kits.


1)High levels of total dissolved solids, from treatment chemicals.
2) Oils and grease from suntan cream, skin cells and body fats.

1)Replace some of the pool or spa water with fresh towns mains water, and treat correctly.
2)Add a small dose of antifoam.

Buy Anti Foam.

A film or 'tide mark' appears at the water line.

Build up of Oils, fats and calcium salts will cause an unsightly 'tide mark'.

1)Reduce the likely hood by asking bathers to shower before using the pool.
2)Remove the deposits with a tile and line cleaning agent.

Buy Tile and Line Cleaner.

Green or blue deposits stain the tile grout and pool fittings.

Over dose of Algaecides.
High calcium hardness levels.

1) Check the pool water copper level, if > 1 ppm, remove a quantity of water to reduce the levels
2) Check Calcium Hardness, remove water if too high.
3) Use an Algaecide that has a stabilised complex.
4)Use a copper free Algaecide.

Buy Test Kits.
Buy Algaecides