Below is a guide on How to Acid Wash a Swimming Pool.
I have also included the video (at bottom) that I created on Acid Washing a Swimming Pool. Remember when dealing with Acid, wear protective gear. I have been in the pool business for over 30 years and in the video you will see I do not have protective gear, however through my experiences I have learned how to hold my breath and walk away from the fumes. I DO NOT recommend this method for you.
You may download and print this Quick Guide: How to Acid Wash a Swimming Pool here [1].
Approximation for a 15,000 gallon pool
Materials:
8 to 12 gallons of muriatic acid
1- 2 gallon plastic watering can
1 qt. BioDex Plaster White and Bright [2] (W&B)
1 qt. defoamer
Sump pump and vacuum or waste hoses (length depends on where sewer line is located. If unable to find pipe, a toilet is a good alternative but be sure to weigh or tie the hose so it doesn’t pop out). In some areas of the country it is illegal to drain your pool water into the street. Check local codes. Some areas have an ‘S’ scratched into the curb which if you follow a straight line towards your house, the sewer drain pipe may be there, near the hose bib.
Drain and rinse pool. Leave an inch or two of water in bottom near main drain to avoid etching plaster. Mix a solution of about 2 T. W&B; 1 gallon water and fill rest with acid into the watering container. This will give you a 50:50 ratio. The soap is very thick, be sure it is mixed well. You can make solution a little stronger but be consistent so the stain removal and end result will be even. If you find the solution needs to be stronger, add water one quarter full, the rest acid. This will give you approximately 1:3 ratio. Main thing is to be consistent.
Rinse area where acid is to be poured. Be sure to wet bottom of pool where acid will flow. As per the video, be sure to pour in a steady manner, paying attention to cover the area completely to avoid any streaking. The solution may stay on for as long as ten minutes (if you use the W&B). During this time you may prepare your next batch.
Rinse the next area, pour, then you can rinse the first section and the second at the same time.
Be sure to follow the acid flow all the way down to the drain to avoid creating a little ravine in the plaster.
When finished, squirt defoamer into the sudsy puddle of water. Drain as much as possible with sump pump. When removing pump, keep it plugged in until it is out of the pool, otherwise the water in the hose will return back in the pool. Either suck out the rest with a shop vac or cut the bottom off of one of the empty gallons of acid and (with the cap on) use that as a scoop which can then be poured into a bucket or empty case of acid.
This is also a good time to check your pool lights and be sure all drain covers are secure and up to new codes for main drain covers. Virginia Graeme Baker Pool and Spa Safety Act [3]
See “Start up Chemicals for Pool Water After an Acid Wash [4]” for instruction on which chemicals to use after it is filled.