does baking soda persist in fish tanks like salt does?

[Thalassa]

Hi,

when dosing with backing soda does it only come out with water changes like salt or does it bind and break down when buffering acids?

thanks

 

[neutrino]

My understanding of alkalinity buffering is that it acts as a sponge. It's not that it breaks down, exactly, but buffering capacity keeps absorbing acids until it reaches a saturation point and then pH can drop. In practice my tanks never reach this point, even with a lot of tannins in some tanks, and pH stays stable even if I skip water changes for a while. That would vary depending on the carbonate hardness in your tank, mine is moderate, not high.

That's the simple answer. I'm not a chemist, but I suspect the extent to which various substances could react with something like sodium bicarbonate (baking soda) to create new compounds depends on the chemicals involved.

 

[Thalassa]

Thank you, this is helpful. I guess i will monitor and adjust as needed.