Guide to Using Muriatic Acid for Pools
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During the course of pool ownership, you will use a wide variety of chemicals and components to keep your system running at optimum efficiency. One of these chemicals that you will come in contact with is muriatic acid. Muriatic acid is used to bring the pH level of your pool down in a controlled manner. To use this pool chemical properly, we explain what muriatic acid is, why would you use it, what it does, how much to use, and what can happen if you use too much.
How Muriatic Acid Affects pH
When you add muriatic acid to a pool, or any body of water, the acid will lower the pH level of the pool. Any acidic substance will lower a pH; lower pH is more acidic, while higher pH is more basic. For comparison, tap water that comes out of your faucet at home should be at a 7 (neutral) and an ideal pH level for a pool is around 7.4 to 7.6.
It doesn't take a lot of muriatic acid to significantly affect the pH of a pool, so it is very important to not add too much, otherwise you risk corroding every part of the pool that water is in contact with.
Starting pH | 10,000g Pool | 15,000g Pool | 20,000g Pool | 25,000g Pool |
7.6 - 7.8 | 12 oz | 18 oz | 24 oz | 30 oz |
7.8 - 8.0 | 16 oz | 24 oz | 32 oz | 40 oz |
8.0 - 8.4 | 24 oz | 1.5 qt | 48 oz | 60 oz |
How to Add Muriatic Acid to a Pool
Make sure pump is on and water is circulating.
Pre-measure the acid to minimize the chance of pouring too much. If you do pour too much in then you will have to either add some pH minus or, depending on how severely the pH lowered, either let it evaporate out or partially drain your pool and refill with new water.
Take pre-measured amount of muriatic acid and walk around the perimeter of your pool while slowly adding in the acid, making sure not to get any on coping stones, patio blocks, or other parts of the pool. If you spill any, put water on the area immediately to lessen the chance of bleaching.
Leave the pool on to mix the acid into the water.
Test the water in a few hours and adjust chemistry as needed.
Warning
It is very important to use proper protective gear when handling any hazardous chemicals, especially acid. This includes using acid-resistant gloves, closed-toe boots, long sleeves, and eye protection. You should also have a source of fresh water nearby in the event that skin or clothing makes contact with the acid.
Tips for Using Muriatic Acid
If any acid at all no matter how small the amount gets on your skin or clothes, wash the area off immediately. Do not wait to see if you feel any effects.
When opening the container make sure that you are either outdoors or in a well ventilated area to minimize how much of the muriatic acid fumes you are breathing.
When pouring the acid into the pool use smooth motions to lessen the chances of splashing on yourself or the surrounding area.
Be sure to measure ahead of time to lessen the chances of pouring too much acid and potentially causing a bigger problem than you are trying to solve.
If you have leftover acid, you can use it to clean parts of the pool by pouring it on and scrubbing, or to get out a stubborn stain (hard surfaces only). Do not use acid on a liner directly.
Frequently Asked Questions
How long does it take for muriatic acid to work in a pool?
Muriatic acid starts working immediately, and once it is fully mixed it will reach full potency in a few hours.
What happens if you put too much muriatic acid into a pool?
If you put too much muriatic acid in a pool, you can corrode all of your pool mechanicals and piping. If this happens it is very important to lower the pH level as fast as possible, either by adding something to raise the pH or partially draining the pool and refilling it with fresh water.
Can you clear a cloudy pool with muriatic acid?
If the cloudiness of your pool is caused by a high alkalinity level which is causing calcium scales, then muriatic acid can clear your pool of cloudiness.
Read the original article on The Spruce.
