Water Chemistry:
Spa water chemistry is both simple and complicated. It can be complicated due to the enormous number of variables that affect water chemistry. It can be confusing, because of the the chemical terms that are sometimes used interchangeably: oxidation, disinfection, hardness, alkalinity...But, once you have made adjustments for those, it is often as simple as adding one or two chemicals a week as I will explain.
But first: The explanation below only applies to a certain type of chemistry that is common in Plumas County. It won't work very well in the Chico area where the water supply is generally very "hard" (high alkalinity and high calcium hardness).
And second: If you have a system that is working for you, don't change it!
In Plumas County, most domestic water is "soft" or "acidic". While this is not good for spa equipment, it simplifies the number of adjustments that need to be made. If we assume that you are using bromine as your disinfectant (see below), we can make it even simpler.
Why Bromine?: Chlorine and bromine compounds are by far the most commonly used residual disinfectants used in spa care. While chlorine is more common in swimming pools (mainly because of cost), bromine has several advantages in spas:
1. Bromine is more stable in hot water.
2. Bromine is more effective at higher pH levels, meaning you don't have to worry as much about balancing pH.
3. When bromine reacts with organic contaminants, the reaction, creating "bromamines" is much less irritating than the "chloramine" reaction.
4. (And most important to this discussion) Adding an oxidizer (non-chlorine shock, ozone...) to water that contains bromamines will result in the "reconstitution" of the disinfecting type of bromine. (Eliminating chloramines requires "superchlorination" which can be tricky in a small body of water.)
So, when I fill a spa in Plumas County, I check the calcium hardness and add calcium chloride to raise the hardness to about 200 ppm (usually takes 1/4 to 1/2#). Then I add baking soda to raise the alkalinity to about 200 ppm (once again, usually 1/4 to 1/2#) and to get the pH up. I add 2 oz. of sodium bromide, and then enough "non-chlorine shock" to clean contaminants out of the fill water and to activate the bromine (several ounces, usually twice the "maintenance" dosage). From the initial balance on, all you have to add to your spa is baking soda when the pH or alkalinity drops too low, and "non-chlorine shock" when the bromine reading is too low. If the readings are too high, do nothing. All of the chemical elements in most of the water around here will tend to lower those readings eventually.
But first: The explanation below only applies to a certain type of chemistry that is common in Plumas County. It won't work very well in the Chico area where the water supply is generally very "hard" (high alkalinity and high calcium hardness).
And second: If you have a system that is working for you, don't change it!
In Plumas County, most domestic water is "soft" or "acidic". While this is not good for spa equipment, it simplifies the number of adjustments that need to be made. If we assume that you are using bromine as your disinfectant (see below), we can make it even simpler.
Why Bromine?: Chlorine and bromine compounds are by far the most commonly used residual disinfectants used in spa care. While chlorine is more common in swimming pools (mainly because of cost), bromine has several advantages in spas:
1. Bromine is more stable in hot water.
2. Bromine is more effective at higher pH levels, meaning you don't have to worry as much about balancing pH.
3. When bromine reacts with organic contaminants, the reaction, creating "bromamines" is much less irritating than the "chloramine" reaction.
4. (And most important to this discussion) Adding an oxidizer (non-chlorine shock, ozone...) to water that contains bromamines will result in the "reconstitution" of the disinfecting type of bromine. (Eliminating chloramines requires "superchlorination" which can be tricky in a small body of water.)
So, when I fill a spa in Plumas County, I check the calcium hardness and add calcium chloride to raise the hardness to about 200 ppm (usually takes 1/4 to 1/2#). Then I add baking soda to raise the alkalinity to about 200 ppm (once again, usually 1/4 to 1/2#) and to get the pH up. I add 2 oz. of sodium bromide, and then enough "non-chlorine shock" to clean contaminants out of the fill water and to activate the bromine (several ounces, usually twice the "maintenance" dosage). From the initial balance on, all you have to add to your spa is baking soda when the pH or alkalinity drops too low, and "non-chlorine shock" when the bromine reading is too low. If the readings are too high, do nothing. All of the chemical elements in most of the water around here will tend to lower those readings eventually.