Hydrogen Chloride- Muriatic acid question

[badpacket]

OK, so I never took Chemistry in school, will basic math suffice?

I have a 72g bow with extensive coraline that I decided would be easier cleaned with vinegar than razor blade. After a little thought, I figured I'd probably need a lot more than a couple of gallons of vinegar to do much, assuming dilution in ~65 gallons of water. So, I finally found a HD with muriatic acid, specifically hydrogen chloride @29%.
If one were to take 1g of 29% hydrochloric acid and mix with 1g of tap water, would you actually have 2g of ~15% acid solution, or does it scale differently?
I know Randy has said a 10 to 1 ration is sufficient, however I really can't believe I would need ~7g of acid for a 72g.... I can afford to wait a bit longer for it to dissolve the coraline, if that means have a higher starting pH.

I ask because I'm confused about acid strengths, as it is not only their pH which is of import, but also the number of free protons????

 

[JC VT]

I would fill the 72 up most of the way with water, throw a power head in, and add in HCl in half gallon increments until you see the results you want. I would also recommend a ventilated area.

 

[wlagarde]

"If one were to take 1g of 29% hydrochloric acid and mix with 1g of tap water, would you actually have 2g of ~15% acid solution" - Yes

 

[Fishie Nut]

If you purchase muriatic acid in a pool store, it's usually 10 percent HCL, so dilution is not necessary. USE rubber gloves and do it OUTSIDE!

 

[badpacket]

Thanks, I was hoping it was something simply like that. I got a quart once from Ace that was 43%, the stuff from HD is 29%. Tank is on the back patio, 2x1g of acid for $7.50.

 

[Randy Holmes-Farley]

The stronger the acid, the faster it will dissolve the calcium carbonate deposits. I usually recommend diluting the full strength (about 30 weight percent) muriatic acid with 10 parts of fresh water, but you can use less if you want to wait longer. In most cases, you need not fill the aquarium to clean it. Just spread the acid solution around with something.
If you do really want to fill it, you can slowly add the acid until it seems to be dissolving the deposits (as suggested above)

as it is not only their pH which is of import, but also the number of free protons????

FWIW, those are the same.

 

[wlagarde]

pH= -log[H+]

 

[JamesJR]

Hydrogen chloride is a gas!

 

[Randy Holmes-Farley]

Yes, hydrochloric acid (aka muriatic acid) is hydrogen chloride (a gas) dissolved in water.

 

[badpacket]

Thanks Randy, I decided to fill it since I didn't want to be sloshing around an acid, or trying to tip the tank in different directions to allow the water too soak the coraline.

I too thought it was odd that the ingredients were labeled as containing hydrogen chloride instead of hydrochloric acid, however, maybe its a CA thing, and it is true....