about kh?

[robt666]

if kh keeps ph stable.....? 

i saw some site it says kh for crs is 0-2

low kh means ph is less stable...?

that makes it unsafe to crs ?

[Mamashack]

My understanding is that KH provides buffering with carbonate and bicarbonate if the pH suddenly drops. CRS need a lowish pH anyway so less buffering is desired in this case. 

[Pika]

There are also other buffers for pH besides the carbonates, so I figure that's gotta play some role in stabilizing when we keep the KH so low.

[Mamashack]

There are also other buffers for pH besides the carbonates, so I figure that's gotta play some role in stabilizing when we keep the KH so low.

You've peaked my curiosity Pika - what other buffers? Genuinely would like to know.

[Pika]

I'm not actually entirely sure on this either, but it's what I've gathered from the fact that KH can stay at near zero while the active substrates will keep pH stable and low.

 

I'm a long way from chemistry classes, unfortunately, but I think sodium (bi)carbonate is only one of many buffers that can help the pH stabilize and not swing wildly. Carbonates are what is measured by the "KH" ("Karbonathaerte" in German or roughly "carbonate hardness") so that's the particular one we focus on. It's also easy to increase by adding standard baking soda from the kitchen pantry to the tank.

 

Phosphates buffer blood and cellular fluid in the body, I think, so that would be another option. Rather than the carbonate molecule, the phosphate does the work.

 

Also, Google-fu provided me a big list of commercially available buffers. along with what pH ranges they are good for. I bet most of them aren't appropriate for a shrimp tank, but the Amazonia people probably figured out which ones are.