Successful usage results ...
First, I want to emphasize how important it is to be careful when using Muriatic Acid (MA)
This stuff will burn through pretty much anything you spill it on;
Carpet, skin, metal, some plastics, your countertops and hardwood floors, cats and dogs, even gerbils
Plus some things it reacts with can become very toxic once airborne and will create some very serious gasses.
Please be super careful with it.
It will displace the oxygen in your lungs, so, if you happen to be exposed to any serious fumes, don't try to breath but walk away while exhaling, and then take some breaths while you're clear of the fumes.
With that said, I used this, and Pure Hydrochloric, along with Phosphoric, Caustic Soda, and straight Nitric acid for 23 years.
You'd think I'd know better ... Well, I spilled some
I was being very careful when measuring out what I needed, doing so inside the laundry tub, and sealed the container very well when I was done.
I then carelessly carried the bucket I keep the MA in, along with a vial of 6.5ml acid, and promptly walked into something in the way, spilling the vial as I went.
Thankfully it only spilled on some crappy old carpet, but it still made a big mess. It burned right through the carpet to the backing before I could grab some water to dilute it.
After trying to soak up the worst of it with some old rags, I shook some baking soda over it and then soaked it with water.
Needless to say, there are big holes in the carpet now
Play safe with this stuff, or it'll bite back
So, I successfully performed my first 'new salt water' acid dosing.
I calibrated my pH probe first, just to be safe
I started with new water at;
Alk 12.1
Ca 370
Mag 1050
Not knowing what would happen to the Ca and Mag after dosing the MA, I decided to bring the Mag up to an acceptable level first. I proceeded to raise it to 1350.
Then I double-checked my Sg and found the Mag had raised it from 1.026 to 1.027. I added some RO to bring it back down, and the Mag dropped to 1290 aarg.
Not going to play that cyclicle game. Back to altering the Alk.
So now I'm dealing with;
Alk 11.5
Ca 360
Mag 1290
The MA I used is from Canuck Tire
Ro-Tyme Muriatic Acid
My formula works !!
I wanted an Alk reading of 7.7, and the formula told me to use 12.84ml of MA, so I started off with 6.5ml
This resulted in;
Alk 9.75, and the pH dropped from 8.1 to 7.1
After waiting 10 or so minutes, I added another 6.5ml of MA
This resulted in;
Alk 7.85
Ca 365
Mag 1290
pH 6.85
I aerated the water over night with an airstone and tonight I tested;
Alk 8.3
Ca 365
Mag 1290
pH 7.82
As you can see, it looks like there is a bit of an adjustment period for the Alk level after using the MA. Overnight it rose from 7.85 to 8.3
IF I ever need to use it again, I'll do the same as this week and let it sit overnight before re-testing the big 3. Then I'll adjust the water as needed at that point.
So, I'm happy to report that using MA to drop Alk is do-able if done safely, and it doesn't appear to adversely affect either Ca or Mag.
I'm actually surprised as I was expecting the Ca to rise as the Alk dropped.