Soda Ash vs Sodium Bicarbonate?

[Randy Holmes-Farley Verified Community Expert]

I have no idea! I don't even test pH. I make sure my Alk, Ca, and Mg are on point and let the pH be whatever it is. I'm not going to chase it anyway.

That certainly is the trendy thing to do. Not sure it is justified, though.

 

[lpsouth1978]

That certainly is the trendy thing to do. Not sure it is justified, though.

Please explain.I have a Pinpoint pH monitor, but I stop using it because I didn't see the point. Like I said, I'm not going to chase pH, so it would really just be so I know what it is at. If there is more to it, I would certainly like to know.

Honestly, I'm not even sure I know of a way to safely manipulate pH, beyond switching to soda ash, and I thought that would just be a temporary increase.

 

[DraggingTail]

Please explain.I have a Pinpoint pH monitor, but I stop using it because I didn't see the point. Like I said, I'm not going to chase pH, so it would really just be so I know what it is at. If there is more to it, I would certainly like to know.

Honestly, I'm not even sure I know of a way to safely manipulate pH, beyond switching to soda ash, and I thought that would just be a temporary increase.

I kinda get it. Mine never moved. 8.2 every time. However, the one time I don't test it will be bad. And it's the easiest test I do so why not

 

[Randy Holmes-Farley Verified Community Expert]

Please explain.I have a Pinpoint pH monitor, but I stop using it because I didn't see the point. Like I said, I'm not going to chase pH, so it would really just be so I know what it is at. If there is more to it, I would certainly like to know.

Honestly, I'm not even sure I know of a way to safely manipulate pH, beyond switching to soda ash, and I thought that would just be a temporary increase.

There are plenty of appropriate ways to alter the pH of a reef aquarium that do not lead to problems.

Some (most?) hard corals will grow faster at high pH, especially some SPS..

Most calcifying organisms will be stressed by having to work harder to calcify as the pH drops, especially at the very low end (say, 7.7 and lower where aragonite can begin to slowly dissolve.)

 

[Randy Holmes-Farley Verified Community Expert]

Baking soda, or sodium bicarbonate, cannot be used as a substitute for soda ash for tie-dyeing at room temperature. This is because baking soda will not produce a pH above 8, while a pH of 10 or 11 works best as a fixative for fiber reactive dyes. Soda ash works much better.

While I think most reefers here understand the pH effect difference between dosing sodium carbonate and sodium bicarbonate, both of which are very useful for alkalinity additions, I will point out that one can readily attain sodium bicarbonate solutions above pH 8.0 (but not above 9).

That said, one of the oddities of chemistry that we encounter is that adding a solution of bicarbonate in water at pH 8.3 to reef tank water at pH 8.1 will actually lower the pH of that water.

Along those lines, adding pure RO/DI water at pH 7.0 to reef tank water at pH 8.0 will actually raise the pH of the reef tank water a little bit.

Gotta love chemistry!

 

[PranK]

Gotta love chemistry!

Dunno about that!

 

[gbroadbridge]

Who uses which and why?

Sodium carbonate (soda ash) is more soluble so you can make a more concentrated solution.

 

[hhaase]

I bake my sodium bicarbonate to make it into soda ash, mainly because I struggle to get above 7.9 without it. Tank is in the basement, as is my gas furnace for heating the house, and due to location I can't run a fresh air line outside to the skimmer.