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Does Water Testing Matter?

Does water testing matter

You may be tempted to skip testing your pool water, but we cannot stress its importance enough. Water testing is essential in protecting not only your investment, but also your family’s health.

Water testing is the first step in ensuring your pool is perfectly balanced. A balanced pool protects your pool equipment, your family against itchy skin and eyes and enables your sanitiser (and other chemicals) to work as effectively as possible.

You should aim to test your water at home once a week, using the BioGuard 6-in-1 Test Kit to ensure your family is swimming in safe and healthy water. We also recommend getting your water professionally tested at least once a month, by your nearest BioGuard Approved Retailer, who has the latest, state-of-the-art water testing equipment and software.

To help you understand how to best maintain your pool during summer, listed below are some terms you should familiarise yourself with, and the levels they should sit at. Detailed descriptions of what each term means are also listed below.

Term How it’s measured
Total Alkalinity Test total alkalinity (TA) first because a correct level will maintain your pH levels. Note, different pool surfaces require different TA levels.
  • Concrete/tiled/pebblecrete: 80 to 125ppm (ppm = parts per million)
  • Other surfaces: (eg fibreglass/vinyl) 125ppm to 150ppm
Chlorine (Sanitiser) 1.5ppm to 3.0ppm
pH pH is measured on a scale from 1 [acidic like lemon juice] to 14 [alkaline like cloudy, soapy water]. Ideal range 7.4 to 7.6
Calcium Hardness Note, different pool surfaces require different Calcium Hardness levels.
  • Concrete/tiled/pebblecrete: 200ppm to 275ppm
  • Other surfaces: (eg fibreglass/vinyl) 175ppm to 225ppm
Cyanuric Acid 30ppm to 50ppm

Total Alkalinity (TA)

TA is the measure of buffering minerals present in the water, these minerals are critical to prevent the pH from shifting or bouncing.


pH is a measure of the acidity of the water and is considered the most critical element of water balance.

  • If the pH level in your water is too low, the water is acidic, causing corrosion, itchiness, sore eyes, over active chlorine and potential equipment damage.
  • Furthermore, a spike in the pH level indicates your water has become alkaline and may start to cloud. Cloudy water leads to a build-up of scale and corrosion of your pool equipment.
  • You can lower pH levels by adding BioGuard Lo’N’Slo™ and raise them by adding BioGuard Balance Pak® 200.


Chlorine is a sanitiser that keeps your pool free of harmful bacteria. If the chlorine level in your pool has dropped, your bacteria levels will spike. We recommend using BioGuard Smarter Sticks® for stabilised sanitation to control bacteria. Unlike traditional chlorine sticks, Smarter Sticks contains SilkGuard, a unique additive that attaches itself to hard water components and metal surfaces, protecting against corrosion and staining. If your chlorine levels need a quick boost, we recommend BioGuard Power Chlor® – it’s easy to use with no need to pre-dissolve, and also improves filter efficiency! Ask your local BioGuard Approved Retailer about the best chlorination solution for your pool or spa.

Calcium Hardness

Calcium hardness is the measurement of how much calcium is present in the water. It’s necessary in your pool, otherwise the water will leach calcium from your pool walls, equipment, and even fingernails! Low calcium levels in your pool water can cause corrosion in your pool equipment, and high levels can create scale. To prevent this corrosion, we recommend using BioGuard Balance Pak® 300 to increase calcium hardness. If you have high calcium levels, we recommend BioGuard Scale Inhibito™ which prevents excess calcium from forming scale.

Cyanuric Acid

The role of cyanuric acid is to protect your chlorine from being broken down by the sun (50% of chlorine is lost to sunlight in just 20 minutes)! Cyanuric acid helps keep your chlorine from breaking down, ensuring your water is sanitised and safe for longer. If your levels are low, we recommend using BioGuard Stabiliser™.

While it can seem like a drag, regular water testing is so important in keeping your pool safe and healthy for swimming. And don’t forget that your water balance is significantly affected by rain, so make sure you test your water after any downpours.

Does water testing matter