Will using ph buffer raise alk temporarily?

[sasscuba]

Does using ph buffer raise alk levels? I tested alk right after using ph buffer and it was much higher than normal...just curious. Thanks.

[bertoni]

All pH buffers add alkalinity. That's why dosing them to solve pH problems tends to cause worse problems.

[bertoni]

Oops, I should have posted this link to an article on low pH problems:

http://www.reefkeeping.com/issues/2004-09/rhf/index.php

[kevin2000]

Yes .. alkalinity is "buffer". Those expensive commerical buffers are just baking soda (bi carbonate), washing soda (carbonate) combined with a touch of boron/borate (20 mule team borax). In general buffers control the PH swings by controlling the CO2 levels within the tank.

[MCsaxmaster]

Agreed. In order to change the pH of the tank you need to change the ratios of alk:CO2. Higher alk means higher pH while higher CO2 means lower pH. You can raise pH either by raising alkalinity relative to CO2 or by lowering CO2 relative to alk.

cj

[kevin2000]

Originally posted by MCsaxmaster
Higher alk means higher pH while higher CO2 means lower pH. You can raise pH either by raising alkalinity relative to CO2 or by lowering CO2 relative to alk.cj

All you need is a reasonable level of alk to control PH .. once you have sufficient alk adding more doesn't lower CO2 or have any long term impact on PH - just throws your water chemistry out of balance.

[MCsaxmaster]

Originally posted by kevin2000
All you need is a reasonable level of alk to control PH .. once you have sufficient alk adding more doesn't lower CO2 or have any long term impact on PH - just throws your water chemistry out of balance.

Alkalinity alone doesn't control pH in sea water...

Adding alkalinity doesn't lower CO2, and unless you are using a hydroxide salt (e.g., Ca(OH)2, NaOH) or a non-carbonate source of alkalinity (e.g., borate) adding alkalinity will add CO2 to the tank water. What is important in terms of pH is, in effect, the alk:CO2 ratio (here I mean total CO2, TCO2--the relationship is actually a bit more complex when it comes to calculations, but this works as a conceptual model). Adding alkalinity will cause a long term rise in pH, if the pCO2 of the atmosphere is not changed and the tank comes to equilibrium with the atmosphere.

cj

[Billybeau1]

And that is exactly why pH buffers are never a good idea to raise pH. Yes the pH will rise but it is very short lived. Usually back down within 12 hrs or so.

Controlling CO2 is the best option in this case.