Forums / TEAM Marine Depot / Pulse on the Hobby – by Steven Pro / Muriatic acid use / Latest Posts

RE: Muriatic acid use

Jansenwrasse — Wed, 16 Jul 2008 17:29:18 GMT

Just be really careful HCl is underestemated, just the vapors from the Acid are enough to put someone in the hospital for a very long time!

Chris you are everywhere aren't ya

RE: Muriatic acid use

jtremblay — Sun, 29 Jun 2008 18:54:00 GMT

Muriatic acid is amazing stuff.

A while back, I had to clean out a restaurant steam table. I was all set to attack it with rubber gloves and a scouring pad when the other cook called me an unflattering name, told me stand back, filled the table half full of water, then poured a jug of muriatic acid into the water.

Fooomf! A couple years' worth of built-up scale was gone in five minutes.

Our boss came back later in the afternoon and was shocked at how shiny it was.

RE: Muriatic acid use

charlesr1958 — Sat, 28 Jun 2008 03:10:33 GMT

Its such a commonly used "cleaner" you can buy it at any store in town, although I had to break Linda's habit of using it to clean the bathroom floor tiles as I now have to re-grout all the tiles... Makes a great drain cleaner though...lol

Chuck

RE: Muriatic acid use

Chris Jury — Fri, 27 Jun 2008 18:34:37 GMT

They're selling 29% HCl in the store?!?!

Holy moly--I'd have on goggles, gloves, and a lab coat and pour that in the fume hood. That's pretty darn strong stuff (38% is the strongest it comes, and that's some seriouly concentrated stuff).

Anyway, best of luck.

Chris

RE: Muriatic acid use

charlesr1958 — Fri, 27 Jun 2008 04:46:08 GMT

Thanks Chris,

I have stopped using the acid for some time now because when I switched to a less opaque mixing container, the color of the precipitation (brown/pinkish) got me very concerned. Having read your posts I am glad I did so as this acid is the super-market variety as they sell it and use it as a daily house cleaner... The bottle(s) state that its a 29% strength in an aquious solution, that solution is what gives me the willys. For now, when I see the calcium unable to be maintained I simply go get some NSW and be done with it. Thanks again.

Chuck

RE: Muriatic acid use

Chris Jury — Wed, 25 Jun 2008 18:25:24 GMT

p.s. As a side note, mineral acids like HCl very readily dissolve all sorts of metals, including somewhat nasty heavy metals and transition metals (silver, copper, cadmium, etc.). Unfortunately, there's not really a way to have any idea how clean muriatic acid from the store is or is not. It may well be just as clean as technical grade or reagent grade HCl (which is probably fine, but far from immaculate), or it may be much dirtier. There are different grades of acid for different applications. HCl for one application will lack contaminents x, y, and z, but will have a, b, and c whereas HCl for another application might be just the reverse.

I bring this up not to worry you, but just to point out that contamination might indeed be an issue. At high pH, many of these metals will precipitate as hydroxides. However, metals tend to show highest solubility at very low or very high pH. For instance, iron will precipitate as FeOH3 at intermediate pH (reaches a minimum at ~8). At low pH it is more soluble because there is little OH- to precipitate with while at high pH (> 12) it becomes more soluble as it forms complexes with more OH- (e.g., FeOH4-, FeOH5--, etc.). The range at which metals are least soluble (and would therefore tend to precipitate with hydroxyls) depends on the metal in question. The OH- from the the Ca(OH)2 may help to precipitate some metals that could be present in the HCl though. The efficacy will depend on pH and on the particular metal.

Chris

RE: Muriatic acid use

Chris Jury — Wed, 25 Jun 2008 18:07:07 GMT

Chuck,

Appologies on getting here a bit late. Kalkwasser shouldn't have the capacity to yield an imbalanc of calcium and alkalinity. What kinds of numbers are you seeing? Do realize that adding 0.5 mmol/l of kalk will raise alkalinity 1 meq/l and calcium ~20 ppm.

Since you're using NSW, at 35 ppt you should have ~412 ppm calcium and 2.37 meq/l total alkalinity. If you raised TA by 1 meq/l with kalk to 3.37 meq/l you'd have 432 ppm calcium. With most calcium test kits, that is just getting to the point where you can resolve a difference. A difference of 1 meq/l alkalinity is readily measurable though.

Using muriatic acid with Ca(OH)2 will ge you CaCl2 (and water) as mentioned. If you need a more potent supplement than what you can get from kalk (e.g., if calcium and alkalinity are chronically low) then making up some calcium chloride (which will also contain some OH- if you use excess Ca(OH)2 ) for calcium and using baking soda/baked baking soda for alkalinity should work fine.

Chris

RE: Muriatic acid use

charlesr1958 — Sat, 10 May 2008 15:57:36 GMT

Thanks, that would be a good thing then...

Chuck

RE: Muriatic acid use

sjames — Sat, 10 May 2008 08:08:18 GMT

to the best of my knowledge, mixing hydrocloric acid and limewater will give you calcium chloride (and more water).

RE: Muriatic acid use

charlesr1958 — Sat, 10 May 2008 05:35:41 GMT

Thanks, the carbon issue was a biggie for me and now just want to reassure myself that I am not creating some exotic compound/chemical by having the acid dissolve the calcium. Am crossing my fingers that it is similiar to what goes on with a calcium reactor. Have been doing so for two weeks now and can not see any negatives and it seems to be doing what I had hoped it would, but...as we all know, the unseen or long term possibles is what gives me the willys. As a precaution, I still add calcium hydroxide untill its at saturation and forms the familiar precipitation that settles out in the hopes that any metals or impurities drop out as well. Even so, where I would get the same precipitation with one teaspoon of powder, with the addition of a bit of acid, it now takes at least four teaspoons. Having my calcium levels in the system jump up instead of remaining at the same level seems to be a good indication as well. I'm just paranoid though...

Chuck

RE: Muriatic acid use

Steven Pro — Sat, 10 May 2008 05:17:37 GMT

Muriatic acid is another name for hydrochloric acid, no carbon there, just hydrogen and chloride.

RE: Muriatic acid use

charlesr1958 — Fri, 09 May 2008 18:55:43 GMT

Thanks Steven, I was also thinking along the lines of vinegar use but had hoped the muriatic would not be a source of carbon as the vinegar is. Just concerned about mucking around with bacterial levels as those who use vodka,sugar attempt to do, but outside of that concern I just want to ensure I am not creating some other compound/metal or something that will make me regret using acid. I am going to try and find calcium chloride as that will raise my calcium levels and not just maintain it. If not then I will have to go back to massive water changes as I really would rather not do something to my system without knowing all the possibles involved.

Chuck

RE: Muriatic acid use

Reefski — Fri, 09 May 2008 18:46:36 GMT

is there no way to get CaCl or baking soda?

RE: Muriatic acid use

Steven Pro — Fri, 09 May 2008 09:05:10 GMT

First of all, chemistry is not my strong point. Perhaps someone else can chime in. Chris, you out there?

Anyhow, I know some folks do something similar using white wine vinegar (aka acetic acid). I have never experimented with either method, though.

Muriatic acid use

charlesr1958 — Fri, 09 May 2008 04:32:16 GMT

First, I have tried to find this info online only to become confused as chemistry has a habit of doing to me and can not find anything definitive (pros/cons).

Having only calcium hydroxide available to me, and feeling dang lucky to have that, I can not maintain calcium levels even though all of my top off is lime water. Which I make by using rain water at a pH of 7.0 in a 6 litre container which barely dissolves half a teaspoon of "kalk" powder, leaving a great deal of it settled out on the bottom. Doing it this way while not maintaining my calcium does slowly jack up my alkalinity to where I either have to stop adding lime water or flush the system with a NSW change. Sooo, lately I have been adding about 30ml of muriatic acid to the rain water which is then able to dissolve 3 teaspoons of calcium hydroxide and not only maintains my calcium but raises it, it also does not mess with my alkalinity level in any great manner as the straight water/powder combo does. In fact, it will over time lower the alkalinity level very slowly to where I can easily adjust it back up a bit by using a combo of sodium bicarbonate and sodium carbonate (1/2 ratio).

Oh, and I quickly learned that if one does use such an acid in place of dissolved CO2, do so in a glass container as the reaction generates a great deal of heat and melted a potable water container I was using (1 litre plastic bottled water container). That or dilute the acid out with distilled water, and wear goggles and have no bare skin exposed, and yes I found that out in my own way, which is always the hard way...

So.... Being somewhat skittish on doing so or continuing to do so, I thought I had better swallow my pride and ask if there is anything I should be concerned about.

Having a gallon or two of the acid, and not wanting to make the two hour trip to the mall on another island, I also tried soaking my carbon in a diluted muriatic acid solution as I read that is what industry does to recycle the tons of carbon they use, am I just wasting my time and acid?

Feeling very much the newbie,

Chuck