It is always best to test first! Muriatic acid can create a hot spot of acid in the water that could potentially burn or irritate your skin. It is best to wait 30 minutes after adding it to your pool. We recommend waiting at least 15 minutes to swim after adding algaecide to your swimming pool.
The pump should run for at least half an hour to thoroughly mix the muriatic acid as it diffuses around the pool. If you'd like to aerate the pool longer and increase the pH a bit, keep running the pump or use an aerator/air stone to oxygenate the pool water.
Check the pH Levels Again
In the event that the sensor readings are still too high, you can add very small amounts of muriatic acid to the pool water until you reach the desired pH. Make sure that you retest the water every 3-4 hours until you have reached the correct pH readings, which can be anywhere from 7.2-7.8.
Let the Muriatic Acid Circulate
Turn on your pool pump and let it run for at least 5 hours before testing alkalinity again. If you have a multiport valve on your filter, set to “circulate” to help the muriatic acid mix in.
How Long will Muriatic Acid Take to Lower the pH Level? It can take a few hours to adjust the pH level in the pool, but for it to really mix in completely with all the water, you would want to give it about 4 – 6 hours before retesting the pH level again.
If your pH reading is above 7.8 and you have a 15,000-gallon pool, start by adding 1 quart (1/4 gallon) of muriatic acid. Then after letting the acid circulate for one hour, retest your levels. If you have a smaller pool, start by adding one cup of muriatic acid at a time. Wait for one hour, then add more as needed.
If you use too much muriatic acid, your pH will drop to dangerously low levels. Metals in your pool, such as railings, ladders, bolts, screws, and other important equipment, can be damaged by low pH levels.
Slowly pour the mixture into the deep end of your pool, and wait a few minutes for the solution to disperse. Wait a few minutes, then turn on your pool pump so the muriatic acid can circulate through your pool's filtration system.
We recommend adding Acid weekly! Adding a little and often is better for your water and can actually save you money overtime. Large doses over longer periods of time take a larger portion of your 'Total alkalinity' away. This way you'd be adding more 'alkalinity up' over the season costing you more.
Your pool is probably a green cloudy mess, so you'll want to add two chemicals to begin the clearing process: Pool Acid – also known as Muriatic Acid. Pool Bleach (bought in the big yellow jugs) also known as Sodium Hypochlorite.
Muriatic acid may damage concrete surfaces, so be careful when pouring it on sidewalks or driveways; new concrete typically does not need to be cleaned at all before applying staining agents. If you do pour some on these surfaces, rinse off with lots of water as soon as possible.
Yes, you can add shock and muriatic acid at the same time. However, it is important to be aware of the potential hazards and take proper safety precautions.
In a 10,000 – 15,000 gallon pool, you should not add more than 2 or 3 cups of muriatic acid in a 24 hour period.
The first half hour is supposed to disperse the muriatic acid, but it's possible that there will still be strong pockets. Even if it's diluted it can still do a lot of damage. It's generally recommended testing the pool chemistry after about four hours. That's a good amount of time for it to have properly dispersed.
If you want to clear the cloudiness in your water, you need to monitor the levels of total alkalinity. If the alkalinity levels in the water rise, it will cause problems such as calcium scaling. Calcium scaling is the main cause cloudiness in the water. You can use a Muriatic acid to correct this condition.
Since your chlorine levels will not return to normal right after you shock your pool, we recommend waiting at least 24 hours to add algaecide.
Health Effects
Skin contact causes severe burns; repeated or prolonged exposure to skin will cause dermatitis. Muriatic acid is harmful if swallowed and may cause irreversible damage to mucous membranes; repeated or prolonged exposure to corrosive materials or fumes may cause gastrointestinal disturbances.
Try to wait at least 10 minutes between adding chemicals to your pool. This is a sufficient amount of time for the chemicals to mix in the water.
Precautions to Take Before Using Muriatic Acid
Get the Proper Safety Gear: This acid will cause burns to the skin and eyes, and its vapors can even damage your respiratory tract. Make sure to cover all exposed skin and eyes, wear acid-resistant gloves, and use a respirator and/or work in a well-ventilated area.
Most experts agree that muriatic acid is the best option to lower the pH and alkalinity levels of your pool water. You can also use it to clean tiles, remove stains, dissolve calcium deposits, and kill any mold and algae leftover in your pool at the end of the year.
Lowering pH In A Pool
Sodium bisulfate and muriatic acid are the two main chemicals used to lower the pH of pool water. In most pool shops and online, these chemicals are called pH reducers or pH minus products. So, if there is a preferred chemical you wish to use, always check the content label before purchasing.
Mix one part muriatic acid to eights parts water, then spray or brush the solution onto the moldy area. Wait a few minutes, then scrub well with a nylon brush.
Muriatic acid is hydrochloric acid and this is quite capable of dissolving many different metals, including iron, chromium and nickel, all of which will turn the liquid green.
To raise or lower pH, a pool custodian simply adds acids or alkalis into the water. For example, adding sodium carbonate (soda ash) or sodium bicarbonate (baking soda) will generally raise the pH, and adding muriatic acid or sodium bisulfate will lower the pH.