The pH of the pool water can drop due to rain or other foreign particles falling into it. The signs that the level is too low are burning of the nose and eyes, itching of the skin and corrosion of metal accessories immersed in water. By regularly performing tests and chemically treating the water you can keep the pH in balance; sodium carbonate is the most used substance to increase it.
Steps
Part 1 of 3: Check the pH of the pool
Step 1. Run a test with reagent strips
Purchase them at a pool supply store, home improvement store, or order online. Follow the instructions on the package; generally, just dip them in water and compare the color with a table in the package.
Some tests involve filling a small tube with pool water and adding a few drops of a substance that changes color based on pH
Step 2. Check chemical levels twice a week
Write them down in a notebook to keep track of changes over time. There are a number of factors that frequently alter the pH of a swimming pool and this is the reason why you should check this often. Record the acidity values in a notebook with each measurement.
Step 3. Your goal is a pH between 7, 4 and 7, 8
The reagent strips change color when exposed to water and the hue assumed corresponds to a level of acidity or alkalinity. Compare it with the table on the package to know the current pH level of the pool, remembering that the ideal one is between 7, 4 and 7, 8. By doing this, you know how many points you need to raise the value.
For example, the stripe might turn a banana-yellow color. According to the table in the package, this color corresponds to a pH of 7, 2; this means that you have to raise the value by 0, 2 points as a minimum and 0, 6 as a maximum
Part 2 of 3: Calculate the Required Sodium Carbonate Dose
Step 1. Calculate the capacity of the pool
If you already know how many liters of water it contains, use the data you have. If you have to perform calculations, you have to multiply the volume by a factor that depends on the shape of the pool itself; once you have calculated the volume, be sure to follow the instructions on the label of the product you are going to use. Each brand has specific dosages based on purity.
- If you have a rectangular pool, the formula for volume is height x length x average depth. If the depth varies gradually from one end to the other, measure the maximum and minimum values, add them together and divide by two to find the average value.
- In the case of a round pool, the equation for the amount of water is: square of the radius x average depth x 3, 14. If one area is deeper than the other, calculate the average value as described above.
- For swimming pools with particular shapes, you have to calculate the capacity for each regular section and add up the results; alternatively, ask an expert to estimate the number of liters of water present.
Step 2. Calculate the sodium carbonate dose
It uses about 170 g of substance to raise the pH of 38,000 liters of water by 0.2 points. Start with this reference dosage and add more carbonate later if you need to increase the level even more.
For example, if after testing the water you have detected a pH of 7.2, you want to bring it to 7.6 and the pool contains 38,000 liters of water, pour in 340 g of carbonate on the first attempt
Step 3. Purchase this product at swimming pool supply stores or online
It may be available under different trade names depending on the manufacturer. Read the ingredient label to be sure the active ingredient is just that; if in doubt, ask the clerk.
If there isn't a pool supply store in your area, try looking for carbonate at hardware stores, DIY stores, or even large supermarkets
Part 3 of 3: Add the Sodium Carbonate
Step 1. Leave the filter running as you go
Carbonate works best if it can circulate throughout the pool. To make sure this happens, leave the filter on on the recirculation setting; if you turned it off to clean the pool, start it again.
Step 2. Prepare a 20 liter bucket and fill it with water
You don't have to throw the soda ash directly into the pool, as you won't be able to mix it evenly enough. Instead, dissolve it in a bucket of water and sprinkle it all over the pool; dilute it with at least 4 liters of water.
It is important to pour the water first and the carbonate only afterwards
Step 3. Measure the dose of carbonate and pour it into the bucket of water
Weigh the necessary quantity according to the calculations described above; you can use a normal kitchen scale or graduated cups. Add the substance to the bucket.
Remember never to put carbonate before water
Step 4. Spread the solution into the pool water
If you have a buried model, walk around the perimeter slowly pouring the liquid; if you have an above ground model, try to squeeze the alkalizing solution around the edge as best you can.
If you wish, use a plastic cup to collect the liquid from the bucket and throw it into the pool
Step 5. After an hour check the pH of the water
Allow the soda ash to circulate throughout the pool and change the pH; after one hour, repeat the test with the reagent strip by dipping it in water and checking that the level has reached the desired range.
Step 6. If necessary, add more carbonate
Typically, no more than 450g are needed for 38,000 liters of water; if you put on too much, the pool starts to get cloudy.
