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So, if you have the °Baume of a known chemical, you could calculate the S.G. From this you can compare the S.G. of the particular chemical and see what the actual %concentration would be. | So, if you have the °Baume of a known chemical, you could calculate the S.G. From this you can compare the S.G. of the particular chemical and see what the actual %concentration would be. | ||
| + | |||
| + | ===Safety Cautions=== | ||
| + | *Wear safety glasses for working with muriatic acid | ||
| + | *Always pour the MA *into* the water, not the water into the MA. | ||
| + | *Do not inhale the fumes when handling muriatic acid | ||
| + | *Nest to handle muriatic acid only once pouring from the jug into the pool | ||
| + | |||
| + | ===Tips=== | ||
| + | *Never pour muriatic acid into a measuring cup; open the jug, float it in the pool, and pour right into the water. Mark jugs with 1/4, 1/2, and 3/4 lines from a stick calibrated once with water, then use that to control how much you put in. It doesn't usually have to be exact. | ||
Example | Example | ||
Revision as of 18:37, 18 August 2019
Muriatic Acid
Muriatic acid is used to lower pH and TA.
Muriatic Acid Strengths
You will find muriatic acid in various strengths. The most commonly found are 15.7% or 31.45%. Although you may find 14.5%, 28.3%, 29%, or 34.6%. Alongside the % strength there may be a Baume (Be) number.
Baume to percent
The °Baume scale is an old antiquated method of measurement of a chemicals Specific Gravity. It was devised a long time ago and is a scaling on a hydrometer which measures the Specific Gravity of solutions. To really make things confusing there are 2 ways of using this scale, one for liquids that are more dense than water and one for liquids less dense than water.[1]
- Liquids with lower S.G. than water, S.G = 140 / (°Bé + 130 )
- Liquids with higher S.G. than water S.G = 145 / (145 – °Bé )
So, if you have the °Baume of a known chemical, you could calculate the S.G. From this you can compare the S.G. of the particular chemical and see what the actual %concentration would be.
Safety Cautions
- Wear safety glasses for working with muriatic acid
- Always pour the MA *into* the water, not the water into the MA.
- Do not inhale the fumes when handling muriatic acid
- Nest to handle muriatic acid only once pouring from the jug into the pool
Tips
- Never pour muriatic acid into a measuring cup; open the jug, float it in the pool, and pour right into the water. Mark jugs with 1/4, 1/2, and 3/4 lines from a stick calibrated once with water, then use that to control how much you put in. It doesn't usually have to be exact.
Example 20° Bé Sodium Hydroxide NaOHSG = 145 / ( 145 – Bé ) = 145 / ( 145 – 20 ) = 145 / 125 = 1.16 If you look at the data of Sodium Hydroxide you will see that a S.G of 1.16 represents a concentration of approx. 15 %
Dry Acid
Dry acid can be used to lower pH and TA. However dry acid contains sulfates which will accumulate in the water. Dry acid should not be used in pools with a SWG.
Dry acid is sodium bisulfate. After dissociation of the acid salt, it leaves behind the sulfate ion. Sulfates can damage concrete & plaster as well as degrade the coatings on SWG plates. At high enough concentrations, sulfates can react with calcium to form spindly, needle-like crystals of calcium sulfate (gypsum). Sulfates can only be removed by draining water. While its use in vinyl pools is typically not as problematic as in plaster pools, scaling of gypsum crystals can increase the risk of liner puncture.[2]
Sulfuric Acid
You absolutely should not use sulfuric acid in a plaster pool with an SWG. Sulfuric acid use can casue calcium sulfate scale. Sulfates are bad for plaster and SWGs.[3]
