Salt Water pH Fluctuations
The most common cause of frustration for swimming pool and spa owners has to do with the ability to balance and mange the pH levels in the water. pH is the measurement between acids and bases in the water and is measured on a scale from 0-14 with the range of 7.2 to 7.8 being ideal for pool and spa water. This is considered pH neutral as this is close to the pH of people so we do not have reactions to acidity or alkalinity in the water. The pH scale is not linear in that a pH of 7 is 10 times more acidic than a pH of 8. This is why the pool and spa water needs to be maintained within a certain range for optimal bather comfort and chemical efficiency.
Common pH Problems
The difficulty with pH is not understanding it, but controlling it. The pH in pool water, and especially in hot tub water is very inclined to fluctuate. These fluctuations cause many problems such as scaling or acidic conditions in the saturation index for the water which can result in a massive amount of damage to the pump, filter and especially heater for your system.
Another common problem associated with pH problem in a pool, and especially in a spa, is rash or dry skin itch. Many people assume that they are allergic or sensitive to chemical sanitizers such as chlorine and bromine however the vast majority of cases where bathers develop these symptoms it is actually a result of the pH being outside the neutral range.
How To Control pH - Total Alkalinity
There is something that is measured in pool and spa water which serves the purpose of helping to limit, or buffer, fluctuations in the pH. This buffer is called total alkalinity. Total alkalinity is the measurement of how much alkaline materials there are in the water. By keeping the total alkalinity in the water between 100-150ppm this will effectively control pH bounce. When the total alkalinity level in the water drops then the pH of the water can change wildly. When something is introduced to the water that has a different pH then the water already has, the water pH will change in the direction of the new substance pH.
The higher that you push the total alkalinity, the more control you will have over your pH and the less pH bounce you will get. Ideally keeping your alkalinity around 125-150 is optimal.
Borate To Control pH Bounce
As a secondary method of control or buffer for alkalinity is the product borate. When added to pool or spa water at the level of 50ppm borate will act as a secondary buffer for the pH making it even more unlikely for the pH to fluctuate or come outside of the ideal range. In addition to this benefit of being a pH buffer, borate in pool and hot tub water at or near 50ppm gives the water a much smoother and much silkier feeling that many bathers describe as being similar to the feeling of salt water pools and spas. The scent added to borate is also light and fresh and similar to baby powder as opposed to other scented agents in the water which have a heavy, often flowerly smell. As a final benefit of borate, it actually helps to maximize the effectiveness of your other chemicals in the spa so if pH bounce is a problem for you then there are many great reasons to consider adding borate to your pool and spa care regiment.
As a final note on controlling pH levels in your pool and spa is to be sure to correct your chemicals in the right order. You should always adjust your chemicals one at a time leaving a 2 hour separation between different chemicals. Additionally upi want to follow the alphabet when adjusting chemicals so start with your alkalinity, then your bromine or chlorine sanitizer and finally the pH. If you take these steps you are sure to keep your pH easily within the optimum range.
Start at the beginning to learn if a salt water system is roght for your swimming pool or spa.