This article looks at the four major water quality tests that you need to do on the water in your swimming pool.

Testing for pH balance in your pool water.

The pH scale is a reading of how acid or alkaline the water in your pool is.

The pH scale goes from 0 to 14 with 7 being neutral. A reading of below 7 indicates that your pool water is acidic while levels above that are defined as alkaline.

You want the water in your pool to have a pH reading of between 7.2 and 7.8 and you have to test and possibly adjust the pH reading of your pool water on a regular basis as everything that goes into your pool has a pH value and so will alter the pH reading to some degree.

You test the water with a simple kit that you can get from your pool supplier.

Using the measured container that comes with the kit you take a sample of water from a foot or so below the surface and then add an indicator solution and compare the colour change to a chart that gives an equivalent pH reading.

If your pool water tests below 7.2 the water is acidic and you should add an alkaline; commonly sodium carbonate, and if the level is too high then muriatic acid needs to be added to restore the balance.

You should test the water once a week as, if the pool is too acidic then the chlorine that you are using as a sanitiser will be lost to the atmosphere and need to be replaced too often plus you run the risk of corrosion on metal parts and equipment.

If the pH is too high, showing that the pool is too alkaline then the water may become cloudy and murky and, once again, the chlorine sanitiser will not be working effectively.

Testing your pool for sanitiser.

The sanitiser levels in your pool should be kept high enough to resist the growth of bacteria and they should be tested regularly using an appropriate test kit from your pool supplier.

You might be using chlorine or bromine as a sanitiser.

Chlorine is best suited to soft water areas as it has less affect on the pH balance or alkalinity. The ideal range for chlorine levels in your pool is between 1 and 4 ppm (parts per million).

Bromine is popular for indoor pools as it is more efficient at higher temperatures but also more affected by sunlight. Bromine levels should be kept at 3 to 5 parts per million.

Testing your pool for total alkalinity.

Total alkalinity is a measurement of all carbonates, bicarbonates, hydroxides and other alkaline substances found in your pool water.

Your pool should have a total alkalinity reading of between 80 ppm and 120 ppm (Parts per Million).

When your pool is within this range, rapid pH changes are prevented and the pool water is stabilised.

If the total alkalinity drops too low then the water may take on a green tinge, bathers might suffer from burning eyes or itchy skin and the pH level may well fluctuate and become hard to stabilise.

A total alkalinity that is too high can result in very similar problems.

However, a well-maintained pool should keep its total alkalinity pretty constant but you should still check once a week as if the total alkalinity does become out of balance it could be a relatively lengthy and slow process to restore it.

Testing your pool for calcium hardness.

Calcium hardness is a measure of how ‘hard’ or ‘soft’ your pool water is.

High levels of calcium can mean that scale may form on the inside of your pool and possibly on the heating elements or inside the pool pump. High levels of calcium hardness can also irritate bathers and cause sore eyes in particular.

If the water is too ‘soft’ then it can corrode surfaces inside the pool.

Your pool supplier will have test kits for calcium hardness and also be able to provide the appropriate chemicals to get your pool water back into balance should that be needed.

We hope that this article has been of use to you and has shown you what basic, weekly tests you should do on your pool water.

All these tests are relatively easy to do and with a little practice and experience, keeping your pool water in balance isn’t that difficult.

However, if you would like help in keeping your pool well maintained, we can help you find your nearest pool supplier and to get that process started just use the find a supplier link at the top of this article.

If there is anything you would like to add to this article or if you would like to leave a comment then please just use the reply box below.