We want to do a no drain acid wash on our pool as well as add borax to the water. What would be the best way to do this for a 12,500 gallon pool? I wash planning to add enough acid to lower the pH to 4.0 and brush for 2-3 days. Then use the Borax to raise the pH back up. Do I have to shut down the pumps during the acid wash, or just bypass the heater? How much acid should I add? I hear some people saying 4-8 gallons, but the pool calculator is calling for 16 gallons. I don't want to waste the money by adding too much or risk ruining the finish.
Acid Wash and borax
- Thread starter Owner/Builder
- Start date
y_not
0
What is your reasoning for acid washing the pool?
I'm assuming it's because of calcium scale build-up. Correct?
You don't list your pool surface type, but since it's free form, I would think it'd be some sort of plaster surface over gunite.
Please provide a full set of test results along with the above information so we can more accurately assist you.
As far as pH goes. The pool calculator is only accurate enough with small changes. Assuming your TA has been tested and entered correctly.
It is always recommended to add only part of your chemical addition. Let the water mix for 30min, then test again. Then add more MA appropriately.
However, there's one problem with this. Your standard pH test kit only goes as low as 6.8/7.0. You would need to purchase a wide range pH test kit from Taylor to be able to accurately test that low. You will also need to maintain the pH as it will want to rise over time. How much, depends on your pool.
All of this assumes a current level of 0ppm borates. If you haven't added any, then you shouldn't have any in there. But if you do, it will effect pH drop with the addition of MA.
Your friends saying that you only need X gallons is incorrect. It's based on the water volume of the pool as well as TA and current pH readings. That's why we have pool calc.
I would only use borax to raise your pH if the amount you need to add won't exceed 50ppm borates. Also, your TA needs to be in-line before you add the borates. Because once you do add them, it is very difficult to adjust the TA levels.
I would suggest instead, using sodium bi-carb to raise your pH and TA, since both will be low from all that acid.
Here's some further info on the matter if you're interested.
low-ta-and-alk-adjusted-to-normal-levels-lead-to-blue-pool-t54194.html#p446033
I would suggest waiting for the experts here at TFP that know about doing no-drain acid washes, to guide you before you begin the process.
I'm assuming it's because of calcium scale build-up. Correct?
You don't list your pool surface type, but since it's free form, I would think it'd be some sort of plaster surface over gunite.
Please provide a full set of test results along with the above information so we can more accurately assist you.
As far as pH goes. The pool calculator is only accurate enough with small changes. Assuming your TA has been tested and entered correctly.
It is always recommended to add only part of your chemical addition. Let the water mix for 30min, then test again. Then add more MA appropriately.
However, there's one problem with this. Your standard pH test kit only goes as low as 6.8/7.0. You would need to purchase a wide range pH test kit from Taylor to be able to accurately test that low. You will also need to maintain the pH as it will want to rise over time. How much, depends on your pool.
All of this assumes a current level of 0ppm borates. If you haven't added any, then you shouldn't have any in there. But if you do, it will effect pH drop with the addition of MA.
Your friends saying that you only need X gallons is incorrect. It's based on the water volume of the pool as well as TA and current pH readings. That's why we have pool calc.
I would only use borax to raise your pH if the amount you need to add won't exceed 50ppm borates. Also, your TA needs to be in-line before you add the borates. Because once you do add them, it is very difficult to adjust the TA levels.
I would suggest instead, using sodium bi-carb to raise your pH and TA, since both will be low from all that acid.
Here's some further info on the matter if you're interested.
low-ta-and-alk-adjusted-to-normal-levels-lead-to-blue-pool-t54194.html#p446033
I would suggest waiting for the experts here at TFP that know about doing no-drain acid washes, to guide you before you begin the process.
