The Difference Between Blue and Balanced Pool Water

woman swimming in blue pool

Contrary to many assumptions, blue pool water is not always an indication of a healthy pool. A swimming pool that is healthy and fit for use by all needs to observe a crucial chemical measurement balance. There are several chemicals used in swimming pool maintenance to ensure the water is balanced for your swimmers. Failure to balance the water, along with having adequate disinfection, filtration, and circulation, can lead to a swimming pool that can be hazardous to personal health, as well as destructive to the pool’s condition.

What affects pool water balance?

Swimming pool water is prone to change in the time between service visits, and this leads to challenges in chemical balancing. Many factors, like changing weather and temperature, a high bather load, and contaminants are going to affect the balancing of your pool water. As such, filtration, circulation, and disinfection, as well as making sure the chemical measurements are in concert, is how you balance your water. Your pool technician has to add enough chemicals to not only balance the water for today but also to ensure the chemicals last for another 7 days until their return. This can be difficult especially with major changes in weather (75 to 90 degrees), a large rainfall, or extra swimmers in the pool (Spring Break).

Balancing pool water:

Ideally, swimming pool water that is balanced should balance pH, Calcium Hardness, total alkalinity (TA) and Salt for salt pools. These are, pH of 7.2-7.8, Calcium Hardness of 200-400 ppm, total alkalinity of 80-120 ppm and Cyanuric Acid or Stabilizer of 80-100 ppm and salt at 2700-3400 ppm for saltwater pools. Chlorine is NOT part of the calculation to measure whether or not pool water is balanced.

This is when you can say your pool water is balanced, or in simpler terms, neither corrosive nor scaling or neither over saturated, nor under saturated. To find out if your pool water is balanced, you can use the various test kits, like this one from Taylor, that retails for $151.59 and are able to show how balanced or unbalanced the water is.

If the pH of the pool water falls below 7.0, this translates to the water being acidic or too corrosive. To correct this, a base should be added to bring the levels up. If the levels go beyond 8.0, it will diminish the Chlorine potency, and this is when the water is said to be basic or scaling. Adding an acid to bring the levels down would better the condition. This leaves the balanced levels to effectively be between 7.2 and 7.8.

Total alkalinity (TA) watches the carbonates, hydroxides and alkaline substances in the water. TA can be balanced by either adding a base to raise it or adding an acid to lower it. Calcium Hardness measures water softness or hardness. If the water is too hard, its appearance would be cloudy due to various minerals being high as well, and their deposits would lead to stains. If the water is too soft, it can corrode the surfaces in the pool. Cyanuric acid or stabilizer helps keep Chlorine in the water for longer periods of time. This works by adding some stabilizer in CL to prevent it from breaking down by the suns UV rays.

The difference between blue water and balanced water in swimming pools:

Balanced pool water has many benefits, with the most important being the health of the swimmer and the longevity or condition of the pool. A pool with balanced water takes care of the swimmers’ skin and overall wellbeing. There are some factors that distinguish the color of pool water from how balanced it is. While many assume these two features complement each other, these facts show a number of ways they don’t work in tandem.

It is very important to keep in mind that the blue color is a reflection of how light interacts with water even while it is true that the blue tint in a pool is significant in telling how clean the pool is. Blue pool water comes about when light interacts with water molecules, and in reality, the blue is determined by the depth of water as it reflects how much of the blue end of the light spectrum has been absorbed. It would be ineffective to rely only on the color of the pool to determine how chemically balanced it is, and for this reason, weekly tests should be done.

Unfortunately, there are many unlicensed pool guys focused on keeping the pool water blue and only treat pools with Chlorine and Acid in order to keep the cost of their service low to the customer.

Blue water only partly signals the condition of the pool, and the safety of its use. The blue color of water in a pool is the first indication that the water is balanced, but even so, testing the water is always advised as there are many changes in color that cannot be noticed by the naked eye.

Blue water in pools is also enhanced by the pools finishes, where you find that most pools are fitted with blue tiles to enhance the appearance. In determining the water balance of the swimming pool, this factor is often confusing and even misguiding, and reiterates the importance of regular testing.

While the benefits of having balanced water may, to some extent, outweigh those of a deep blue colored pool, the color is also an important indicator of a healthy pool. Research has shown that other colors, like green, in a pool indicate the emergence of algae which is a clear indication that a pool is not fit for use. A presence of other minerals in water can also reflect a different color.

It is vital, as a swimming pool owner, to know the needs of your pool. Quality maintenance is the only guarantee to a pool’s longevity and your health concerns. It is also the only way to preserve your equipment. The allure of a sky-blue swimming pool is what makes everyone want to have the pool for summer. Ensuring the water is chemically balanced is also as important, and it is what everyone should look out for when choosing a maintenance plan in addition to shopping for a competitive price.

Unfortunately, there are many unlicensed pool guys focused on keeping the pool water blue and only treat pools with Chlorine and Acid in order to keep the cost of their service low to the customer. This approach may be saving you money with less expensive pool service in the beginning but it will have long term effects on the quality of the water, your experience while swimming and the life expectancy of your pool equipment and the surface of the pool because they are only focusing on 1 of the aspects (pH) that make up proper water balance. Chlorine is NOT part of the calculation to measure whether or not pool water is balanced.

Having a professional team to help you maintain your swimming pool is the best thing you can do for your family or association and choosing the team that knows the dynamics of chemically balancing the water will pay for itself in the long run. We have for over 30 years now prided ourselves in ensuring your swimming pool is the talk of your backyard, and to this effect, we offer weekly visits to maintain your equipment and clean your pool to the highest standards in the industry. For accountability and professionalism, we issue Water Balance reports sent by your technician after every visit, complete with pictures of the pool after our Certified Pool Operators clean it.


Bryan Banta, President of B&B Pools, Inc. &  a Certified Pool Operator