Total Alkalinity is a measurement of bases and total dissolved solids in the water, expressed in parts per million (ppm). These bases are bicarbonates and carbonates that act as a buffer systems and help prevent drastic changes in your pH, and prevent your pH from ‘locking’.
If your Total Alkalinity is too low, your pH can change dramatically, and bounce all over the pH scale. Having a low alkalinity can also lead to corroded metal equipment such as jets and pipes, and skin and eye irritation. If your Total Alkalinity is too high, it can cause your pH to lock at the high end of the scale, which means an excessive amount of the chemical pH Reducer or pH Down will be needed to bring it down to the correct amount on the scale, and prevent the water quality issues associated with a high pH reading, such as an odour, and skin, eye and chest irritation.
Balancing Total Alkalinity in your pool, spa, or swim spa, before adding any other chemicals or balancing any other element, gives you the power to control the pH. This is similar to how a thermostat can control the temperature in a room. The ideal level of Total Alkalinity varies with different chemical systems and can sometimes vary with different pool, spa and swim spa manufacturers and surfaces.
If you have a standard, acrylic surface spa or swim spa and are using Crystal Waters Pool and Spa Solutions, we recommend that your Total Alkalinity reads 120ppm – 150ppm. (ppm = parts per million.)
If you have a pool and you’re using Crystal Waters Pool and Spa Solutions, we recommend your Total Alkalinity reads 60ppm – 200ppm.
When balancing your pool, spa, or swim spa, always balance alkalinity first. pH and Alkalinity work together so each of the following products added to the water will control both the pH and Alkalinity. Commonly we see a low, or in balance Total Alkalinity and a high pH, especially in spa water. If you’re using a Crystal Waters chemical system for your spa, or swim spa, and you have a reading demonstrating a low-average Total Alkalinity and a high pH, we recommend bringing the Alkalinity up to around 200ppm and shortly after, bringing it back down, with the pH, as they will come down together. This is particularly important in Spas as the body of water is so small. Please follow our Spa Balancing Cheat Sheet for more information.
To further understand how Total Alkalinity effects the pH scale, you need to understand pH. pH is a measurement of how basic (full of bases – AKA alkaline) or how acidic (corrosive) the water is. 7.0 is neutral, pure water, in the middle of the scale A pH value below that, the water becomes corrosive and damages metals, and a pH higher than 7.8 can form scaly deposits and cause sanitiser inefficiency and bather discomfort.
Now imagine this scale as a see-saw with 1 person from the Base family on one side, and 1 person of equal weight from the Acid family from the other. This scale is balanced, however this is a very low alkalinity as there is only 1 member from each family on board, and if one person got off, the scale would be thrown out of balance. An example of a high Total Alkalinity and a better water balance (120ppm – 150ppm), would be if there were 10 people from each family on the see-saw. If one got off, the scale wouldn’t be thrown out, it would still stay relatively balanced.
This does not however mean “the more, the better”. While each pool, spa and swim spa manufacturer has their own recommendations for the correct level of Total Alkalinity, most commonly 120ppm – 150ppm is considered in balance.
To balance your Total Alkalinity the following products are required:
Crystal Waters Pool and Spa Solutions – pH and Alkalinity Enhancer for spas and swim spas, and Crystal Waters Pool and Spa Solutions – pH Buffer for pools, will raise your Total Alkalinity.
Crystal Waters Pool and Spa Solutions – pH Reducer for spas, and Crystal Waters Pool and Spa Solutions – pH Down for pools and swim spas will lower your Total Alkalinity.