Ph and argagonite

[Cory]

At what ph does aragonite begin to dissolve? If i had 1 micron particles of it, would it dissolve at slightly lower ph?

 

[Randy Holmes-Farley Verified Community Expert]

It depends on the alkalinity and calcium too.

At 7 dKH and 420 ppm calcium aragonite will dissolve at pH values below about 7.7, although it may be very slow at a pH of, say, 7.6 or 7.5.

 

[Cory]

Hmm. What if i had a two ton sand bed, with tank water running through it, would it maintian calcium and alkalinity?

 

[Randy Holmes-Farley Verified Community Expert]

Hmm. What if i had a two ton sand bed, with tank water running through it, would it maintian calcium and alkalinity?

Nope.

 

[Cory]

Nope.

What if it was anoxic and low ph from bacteria?

 

[Randy Holmes-Farley Verified Community Expert]

If it got to low enough pH, yes. I do not know if larger size will accomplish that, however. Too big and there won't be enough nitrate or organic matter in the water to drop the pH enough to dissolve the CaCO3 (unless you dose them, then it might).

 

[Cory]

But flow rate would need to be adjust for delivery of alk and calcium too i guess.

Nice new intuitive article on ph!

 

[Randy Holmes-Farley Verified Community Expert]

Yes, you'd need to control all of the nitrate addition, the organic addition, and the flow.

Why not just use CO2.