Keeping your pool chemically balanced regularly will not only ensure your water is clear and healthy to swim in, but it will also save you money by making your pool chemicals work together, rather than 'chasing' the perfect balance.
If your water is correctly balanced, this means that the water’s chemical demands have been met. However, if chemical levels are out of the ideal ranges, the water can affect other areas of your pool or spa. For example, it could seek the missing elements it needs by attacking or depositing additional elements onto the surface & equipment which can lead to more expensive problems later if not corrected.
Also, if not properly balanced, the sanitising process (killing bacteria and algae) can be impaired.
The main 'variables' in your water balance are:
pH - Potential Hydrogen
pH ranges from 0-14 with 7.0 being neutral and values below 7 being acidic. The ideal range for your pH is between 7.4 - 7.6 for pools and 7.6 - 7.8 for spas. When your pH is within these ranges your, sanitiser (chlorine) most effective and therefore keeps your pool free of algae.
Read a more in-depth description of pH
Chemicals we use
Balance Pak 200 for raising the pH
Lo’N’Slo for lowering pH
TA - Total Alkalinity
The ideal value of Total Alkalinity is 80 - 125ppm in pools and 100 -120ppm in spas. Keeping your Total Alkalinity within these ranges will stabilise your pH levels. When your TA is low, your pH will fluctuate a lot and therefore reduce the effectiveness of your sanitiser and can cause mild skin & eye irritation.
Read a more in-depth description of Total Alkalinity
Chemicals we use
Balance Pak 100 for raising Total Alkalinity
Lo’N’Slo for lowering Total Alkalinity
Ca - Calcium Hardness
This is a measure of the amount of dissolved calcium in your pool water. Depending on your pool surface, we recommend a range between 200 - 250ppm. When the Calcium level is too low, the water will draw calcium from the surface of the pool causing deposits to form. Similarly, if the calcium levels are too high, this will form hard, unsightly deposits on the surface of the pool and equipment.
Read a more in-depth description of Calcium
Chemicals we use
Balance Pak 300 for increasing calcium hardness
Stabiliser - Cyanuric Acid
Cyanuric acid or, as it’s more commonly known ‘pool sunscreen' is used as a chlorine stabiliser in swimming pools to reduce chlorine loss due to UV rays (sunlight) if there is no pool cover. Levels should be maintained at approx. 30 - 100ppm. When your stabiliser levels are low, your sanitiser will not last as long in the water and therefore you won’t get effective algae control. If levels become too high, this can block the sanitiser from being effective also.
Read a more in-depth description of Stabiliser
Chemicals we use
Stabiliser prevents chlorine loss due to sunlight
*Values are approximate ranges that are dependent on your pool/spa type, other balances and factors.
For more information about your pool water balance, speak to one of our knowledgeable staff by calling us on (02) 6021 8700 or ask us a question on our Facebook page HERE.
Technical in-depth chemical balance explanations.
pH
The pH reading tells us whether the water is acidic or alkaline and incorrect levels may cause itchy skin and red eyes. The pH level ranges from 0 to 14, with 7.0 being neutral. Values below 7.0 are acidic. However, what is commonly overlooked is the understanding that pH is probably the most important factor to be considered when balancing swimming pool water.
The Australian Standard for pool water is between the range 7.0 to 7.8 with us recommending 7.4 to 7.6 depending on your pool/spa type. The pH level can change after heavy rain, heavy pool usage, topping up the pool, or adding chemicals, which in turn affects sanitising and therefore should be checked and adjusted frequently.
The effect of pH variation is most noticeable in the effectiveness of your chlorine to sanitise your pool. A typical domestic pool will aim for a chlorine level of about 1-3ppm.
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TECHNICAL: Free chlorine is a measure of both Hypochlorous Acid (HOCL) and Hypochlorite ions (OCL-). The Hypochlorous Acid is the active part of the free chlorine which does the oxidising and destruction of contaminants. The Hypochlorite ion is inactive and can be considered the “reserve” that converts to Hypochlorous Acid as required.
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When your pool has a pH of 7, the free chlorine has 75% Hypochlorous Acid (active) ions. If your pool has a pH of 7.8, the free chlorine has just 28% Hypochlorous acid (active) ions, making your sanitiser much less effective.
Therefore a swimming pool with a pH of 7 and a free chlorine level of just 0.5ppm has the same sanitising effect as a pool with a pH of 7.8 and a free chlorine level of 1.35ppm.
This is why the pH of your pool is really important.
T.A - Total Alkalinity
This is a measure of bi-carbonates, carbonates and hydroxides in the pool. We usually suggest 80ppm to 125ppm is the accepted range, depending on the other balance factors and pool/spa types. We can help you find the recommended level for your pool.
Low Total Alkalinity will lead to erosion of pool surfaces and corrosion of equipment. It will also cause the pH levels to be very unstable so small additions of other chemicals can result in major shifts in pH which is sometimes known as “pH bounce”. A low Total Alkalinity can also cause mild skin irritation and itchiness.
Adding BioGuard Balance Pak 100 will RAISE the Total Alkalinity. Hydrochloric acid will LOWER the Total Alkalinity and the pH so these two chemical components need to be adjusted together.
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TECH TIP: Hydrochloric acid must always be diluted (one part acid into ten parts of water) before being added to the pool and always add acid to water, never water to acid to avoid splashing onto yourself, others or surroundings.
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When topping up the pool, depending on the Total Alkalinity of the top-up water and the amount of topping up, this will affect the Total Alkalinity of the pool water.
Calcium Hardness
This is a measure of the amount of dissolved calcium in your pool water. Depending on your pool surface, we recommend a range between 200ppm and 250ppm for a typical concrete, marbelite or pebble pool. Calcium Hardness cannot usually be tested with the standard test kit so you will need to bring in a water sample to us for testing.
In most pools where calcium levels are not naturally high, you really only need to test a few times each year unless you are using Calcium Hypochlorite to sanitise your pool. This chemical raises Calcium Hardness levels, so more frequent testing and balancing may be necessary.
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TECH TIP: When adding chemicals we suggest increasing in small amounts, running the filter and testing the effect after several hours to avoid overdosing or encountering other problems.
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If the correct balance of Calcium Hardness is not maintained, just like with Total Alkalinity, low levels cause corrosion to the pool surfaces and equipment and high levels will lead to scale formation. Use BioGuard Balance Pak 300 to increase your calcium hardness levels in your water.
Cyanuric Acid - Stabiliser
Cyanuric acid or, as it’s more commonly known ‘pool sunscreen' is used as a chlorine stabiliser in swimming pools to reduce chlorine loss due to UV rays (sunlight) if there is no pool cover. It should be added to the pool and maintained at approx. 30-100ppm. It binds itself to free chlorine and then releases it slowly to minimise degradation by UV light, extending the time needed to deplete each dose of sanitiser.
If the levels become too low, the effectiveness of your sanitation will be reduced because the free chlorine is being broken down by UV light, which leads to the potential increase of algae growth.
On the flip side, if you regularly use powdered stabilized chlorine to sanitise your pool, your stabiliser levels can get too high and this can effectively block your sanitiser from being effective.
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TECHNICAL: The higher the level of Cyanuric acid, the more it reduces the effectiveness of free chlorine. To offset the loss of sanitisation power of free chlorine in stabilised outdoor pools the minimum concentration of free chlorine must be kept between 2ppm and 3ppm (ppm= parts per million).
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Interestingly, Cyanuric Acid is not consumed or lost from swimming pool water unless due to splashing, backwashing or the introduction of freshwater, these are the only times that you’ll need to add more Cyanuric acid.