Where to Find Muriatic Acid

Muriatic acid.

Danny, On one of your episodes, Joe Truini said that muriatic acid would remove scum and water deposits from tile in a bathroom. What I need to know is where can I purchase muriatic acid? – Denise

Hi Denise,

Muriatic acid is used to remove excess mortar from bricks and to balance the pH of swimming pools, so it can often be found at both home centers and pool supply stores. Look for it in the building supply or gardening sections.

Muriatic acid is strong stuff, so be sure to read all the precautions and follow directions including wearing rubber gloves and eye protection. Dilute it with water following the directions on the container before using and make sure there is adequate ventilation.

You can read and watch the video on Joe Truini’s method of cleaning bathroom tile with muriatic acid on our website at How to Clean Tile with Muriatic Acid.



  1. danny can you use muriatic acid on the one piece fiberglass tub enclosure? have tried everything else to remove hard water spots aand soap scum thank you love your website

  2. I have a tile shower. Where the wall meets the floor, I have the ancient problem: Caulking deteriorates and wanter seeps below the pan, not to mention meldew buildup. I want to do thios right and not often have to re-do it.
    I have been advised to:

    1. Use grout and epoxy mixture n the seams. I can get it at Lowes.
    2. Muratic acit to clean the tile scul.
    Also, I have a few tile cracking at the threshold area, corners, etc so I am removing them, ibncluding the Duroc and thin set, and starting fresh in the threshold with net tile.

    While doing this I want to redo it right and correct errors of past.

    Any thoughts??


  3. Muriatic Acid is in the paint dept of my local Lowes store. I just bought a gallon for $6.98 today. Hope this helps.

  4. Can anyone buy muriatic acid in N.Y. State? I heard that you have to be a contractor.How about the states of Connecticut and Mass?

  5. I want to clean around the rim of a toilet. I also want to clear a possible partial blockage as the toilet only flushes COMPLETELY one out of three or four times. This makes no difference whether all liquid or semi-solid waste. I have asked whether just ANYONE can buy muriatic acid in New York State. I have heard about something called IRON OUT. Can you tell me anything about it?

  6. Home depot have stopped stocking it HAZMAT issues. Hardwear stores ACE etc or pool suppliers: ths is the best stuff when used properly

  7. Why has the price of muriatic acid gone up so much lately?

    I put a pool in 4 years ago and used to by muriatic acid at Home Depot for less than $5.00 for a 2-gallon box. The las time I bought it I had to pay $8.99. I’ve also noticed that it doesn’t have the same strong smell that it used to have and it takes more to keep the pH in my pool where it should be. So it would seem it’s getting weaker as well as more expensive.

    Does anyone know why this is or any more about it?

  8. muriatic acid has gone up in price because of new hazmat laws and shiping is stricter.

    it is weaker because of terrorist threat it is easy to make into a weapon.

  9. i heard from someone, forgot the name, but they told me lime a-way is much safer and cheaper. it contain all the ingredients of muriatic acid. i think all the general stores sell lime a-way. there is no laws to stop it. please research oxalic acid, it is good too on all rusts.

  10. Muratic acid is availible at every pool supply store I’ve ever been to. I haven’t been to a pool store in years though.. I don’t know if new regulations have forced it out, but I know it used to be a key component of maintaining a pools ph balance.

    Typically, it’s in a red plastic bottle that should be returned for a deposit afterwards. (don’t just throw it away… by returning it, you are disposing of it properly.

    Don’t forget to dilute it though.. I beleive the mixture is prediluted a bit when you buy it, and messages above mine seem to indicate that it’s even MORE diluted than it used to be.. but you should probably dilute it even further, to see how well it works and then build up the strength if you need to.

  11. White Vinegar is a cheap alternative to muriatic acid, since muriatic acid is about a 25 percent dilute of hydrochloric acid in water, vinegar is about 8-10 percent hydrochloric acid dilute and can be used to achieve a much similar affect.

  12. White vinegar is _NOT_ the same as muriatic acid. Muriatic acid is diluted hydrochloric acid (HCl) and white vinegar is dilute acetic acid (CH3COOH). HCl is a strong acid and is fairly caustic whereas CH3COOH is a weak organic acid and is weakly caustic. While they may be used to achieve a similar effect in some situations, they are not the same thing and when faster a, stronger effect is desired HCl is the way to go.

  13. Hi there. We are trying to get the old rust stains off the top of our retaining wall (concrete) from the rusted old iron railing. What do you suggest to use and will pressure washing help?

  14. Have tried just about everything to no avail to remove hard water/rust stains in toilet. Purchased muriatic acid from a Do It Best hardware store on the advise of a plumber. Worked like a charm. Been years since I’ve seen the white bottom of the toilet bowl!

  15. I was hunting around for Muriatic acid to soak some spa filters in to remove deposits. Instead, I diluted a $1 bottle of “The Works” toilet bowl cleaner (which is a mix of HCL and other ingredients) and it worked like a charm eating off deposits. Filters are like new.

  16. Masonry supply outlets sell Muriatic Acid. Masons use it to clean excess mortar off bricks. I am using it to lower the PH in our pool. Way better to buy a gallon at a contractor’s store than to go to a pool supply store and be ripped off. Another example: Bicarbonate of Soda (Baking Soda), used to balance your pool water costs $3.69 for a 4lb box of Arm & Hammer at the grocery store . The Pool Supply store, with its pretty packaging, gouges customers for $12.50/4 lb box.

  17. Hi, I spilled a litre of muriatic acid in my car over 2 months ago, it seems to have evaporated but right now everything in my car (work van) is oxydating ( rusting) is there something to neutralize the remaining (concentrated?) acid with. Thank you.

  18. Muratic acid may be used to lower the ALKALINITY, not the PH of pool/spa water. Soda ash or sodium carbonate is used to raise PH. It is usually used as a last resort. Baking Soda (sodium bicarbonate) can be purchased at Sam’s Club type stores in 12lb. bags for about $7 – a great price compared to pool chemical suppliers. Baking soda is used to raise the ALKALINITY of pool/spa water.

    • pH is the measure of the acidic or basic (alkali) nature of a solution based on the concentration of hydrogen ions. pH is expressed using a scale ranging from 0 to 14, with 0 being highly acidic, 7 neutral, and 14 a strong alkali. Examples of acidic solutions (from strong to weak) include battery acid, lemon juice, and vinegar. Examples of base (alkali) solutions (from strong to weak) are lye, bleach, household ammonia, and baking soda. Distilled water is considered neutral. The pH of a pool is adjusted by adding either acidic or basic chemicals to keep it balanced in a range between 7.2 to 7.6, making it slightly alkali.

  19. February 5th, 2010 at 1:51 am
    This is a question I have. Last fall I chose a color from the computer to paint and trim my house in. The color and trim turned out to be all wrong and my husband was told to spray it on and it would be faster. The overspray got on the stone and brick pretty bad and the paint color is all wrong for the color of the brick and stone. We live here in Mobile. My husband and I both have back trouble and we bit off more than we could chew with this home improvement venture. Any advise on what we could do?


  21. we used muriatic acid to clean a stone wall and some of the rocks had copper in them and turned green…how do i clean the green off

  22. When my washer is in the spin cycle and draining, the water is backing up the drain and not going down fast enough. Can muratic acid be used to unclog the drain?

  23. Where can I get muriatic acid at 40% HCL concentration. I need it to remove the autocoxic fruits from the seeds of pokeweed that I want to plant. Without the acid treatment I have been totally unsuccessful in germinating such seeds; and of course those that are so treated by passage through the digestive tracts of the small animals that eat them sprout wherever the animals have dropped them on my property. Unfortunately those that sprout never fully succeed in my efforts to transplant them so I want to resort to the same methods used by commercial propagators of pokeweed. Where can I buy this concentration at a reasonable price I’d only need a few ounces.

  24. when my washer is draining, the water is backing up and overflowing. The washer is near the kitchen and the kitchen drain seems to be involved also. Can I put muriatic acid in the washer drain to upstop it?

  25. Its been 8-9 yrs ago that I used a product I think was Muriatic Acid to DE-Silver a mirror, or a part of a mirror, it worked great–had to wear glasses and wear gloves. Is the Acid now as strong as it was then? I bought a product that they called “ego friendly” muriatic acid, but it didn’t work. Web sites offering alternatives to use to de-silver mirror, but just not working. Please help.

  26. Folks, muriatic acid is a very common chemical. It’s in many products you probably already have in your house. It can be found in some products made by Lysol, Lime-A-Way, Liquid Vanish, Sparkle, Zep, etc. Check out the link that ‘jeff’ added above and a similar link I added here:


    And, check out this tragic story from Indiana–this stuff is serious and should be handled accordingly–it can be lethal:


  27. As a former pool builder I used Muriatic Acid to etch new concrete so that it will accept masonry paint. Contrary to what Jeff said earlier… Muriatic Acid is not the same as Hydrochloric Acid. Muriatic Acid is a “watered down” product made from Hydrochloric Acid. Normally, Muriatic is about 30% Hydrochloric and 70% fillers.
    Great caution should be used when handling and using this stuff and I would discourage anyone from using it inside the home without extreme ventilation. Even when used outside on concrete pools the fumes can be overpowering.
    Muriatic Acid is used by cement mason’s to clean concrete and brick surfaces, and it does a wonderful job. This stuff eats calcium like candy, and cement finishes can be permanently ruined if a professional doesn’t handle its use.
    If you do decide to use it yourself remember this… Muriatic Acid is neutralized with a strong mixture of AMONIA & WATER.

  28. If I remove the pressure valve and disconnect the water line from my hot water heater and drain it halfway, can muriatic acid be used to clean the scale out of the inside?
    I read on the internet that this works!

  29. I have gotten excellent results removing scale buildup from toilets using cheap cola. I drain the toilet and pour in 2-4 liters and let it sit overnight, then scrub in the morning before I flush it.

  30. Im going to use it for a science project at my middle school. I bought it at Frys’ Marketplace for about 10 dollars. I also found it at Home depot and it was 10 dollars for 2 gallons. My question is, is muriatic acid the same thing as hydrochloric acid ?

    • Hi Luis,
      Yes, muriatic and hydrochloric acid are the same chemical. Both are available in different strengths. Be careful when working with muriatic acid, and be sure to wear protective clothing, rubber gloves, and goggles, as it can burn you! Good luck with your project!

  31. hi i am going to refine gold out of microchips and electronic parts and i need hydrochloric acid 15%-30% will they sell it at home depot or pool supplies stores? Thank you

  32. Will muratic acid clean scum , and lime buildup off aluminum pontoons , without eating aluminum, or will it hurt my concrete driveway when it drips off pontoons?

  33. I have use it to clean heat exchangers to get the junk out of the 1/4 inch holes and works great at 20% I want to use it to clean my aluminum siding but brake it down to 15% and then paint my house… They use it to wash big trucks so I am going to try it what your thoughts.

  34. I have 1 to 2 million used bricks in piles and I’m looking to clean off the mortar the easiest way possible and then sell. Muriatic Acid seems to be the best way along with a wire brushes & a small hammer/chisel. Any suggestions or advice since I am definitely a beginner in this area.


  36. I found all questions etc. very informative. However, I did not find anything resembling my problem. I have a small fountain, the flow of which is enclosed in a circular block. I have replaced the pump and used everything I could think of to flush out the interior, it still refuses to push up the water I am thinking to soak the whole thing in muriatic acid, it is fairly small and it can be placed in a foot bath container. this will be my final attempt, what do you think? I have seen it flowing properly in the past. a.f.

  37. Will muriatic acid damage a fiberglass hot tub finish? I want to use to clean the water line build up that I can not get off with any other cleaner.

  38. For 25 years I have running the brine solution used to backwash my water softener into the sump hole in my basement floor. Now it no longer flows out fast enough to keep the sump pump from coming on. Will muriatic acid clean the accumulation of salt and hard water scale and make this flow again?

  39. Condensation from crock pot with pork shoulder picnic dripped onto UNSEALED ceramic tile outside on the back patio. So there are now dark blotches on a few tiles. Have tried various cleaning options .. vinegar, diluted liquid bleach, peroxide, baking soda … oxygen bleach is next. Would muriatic acid (diluted) be effective here? TIA

  40. My daughter wants to do a science project and needs to “simulate” stomach acid which has a ph of about 1…is muriatic acid the way to go or could white vinegar be used and achieve the same ph? If we do buy muriatic acid, and test strips, if the ph isn’t right how would we adjust it, is it as easy adding the acid to water to dilute it? what if the ph isn’t low enough?


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