Why did my ph shoot up so fast when buffering with seachem alkaline and acid buffers?

[faebugz]

Arthur, my smaller axolotl I rescued a couple months ago, has been living in a 5.5gal tank temporarily while he grows, before he joins Lavender in her 30 long. The 5.5 is starting to become obviously too cramped for him, so I made a divider for the other tank and prepared to add him in.

Luckily I checked the parameters first, because they were really different. I didn't want to shock his system, so I began trying to slowly adjust his up to meet hers. For reference, my water out the tap is ph 7-7.2, gH 2, kh 2-3.

Used seachem equilibrium, acid buffer, and alkaline buffer. The instructions are pretty confusing imo but this is what I ended up doing.

September 04

Arthur (3.5g)

pH 6.8/kH 2/gH 2
*
Lavender: (25g)

pH 7.6/kH 5/ gH 4

So to Arthur's tank I ended up adding .21g of alkaline buffer and .11g of acid buffer. Plus .65g of equilibrium.

On September 06, I measure Arthur's tank again and got

pH 6.9/kH 2/ gH 3

Not sure why kh wouldn't budge and ph moved so slowly. I decided to up my dosages a little. This time, I added .45g alkaline buffer, .20g of acid buffer, and again .65g of equilibrium.

September 07, today.

I just checked his tank again, and this is what it's at now.

pH 7.4/kH 10/gH 4

Whaaaaat?? Why did it jump so much? My ratios are very similar to before.

Is it safe to keep him in there? Should I dilute it? Or just say screw it and throw him in with lavender at this point?

 

[Murk]

I'm not sure I understand the issue. You had slightly acidic pH, then you added a lot of pH buffer, and now the pH is closer to neutral.

Isn't that what you wanted when you added the buffer?

 

[chicco]

Simply, pH is measured on a inverse log scale so once you break buffering capacity.. it will rise or drop quick.
of note, I’m not a fan of these ion solutions purely because there is little regulation oversight… if you want a gradual increase in pH, GH and KH.. add stones..a common one is limestone (you can even buy pebbles and put it in the filter). However, many other stones can get the job done.. the only issue is.. what other metals could the stone be leaching?… I run an ICP test after two weeks to see… if it’s higher in heavy metals.. ditch the Rock and pick another or do frequent water changes.
If you’re in a time crunch, I would start mixing spring water to your treated water and test the chemistry.. chances are you’ll be somewhere in between.
Just a thought.

 

[faebugz]

I'm not sure I understand the issue. You had slightly acidic pH, then you added a lot of pH buffer, and now the pH is closer to neutral.

Isn't that what you wanted when you added the buffer?

Seachem alkaline buffer and seachem acid buffer are two different products that you are supposed to be able to use in tandem to achieve a gradual shift in ph. With alkaline buffer raising the kh and acid buffer consuming it. It provides a chart for you to calculate your dosage:

My goal was to slowly, in a way that is safe for the current tank inhabitant, raise the pH to match the other tank he would be going into. 6.9 to 7.4 in one night is not slowly

 

[faebugz]

Simply, pH is measured on a inverse log scale so once you break buffering capacity.. it will rise or drop quick.
of note, I’m not a fan of these ion solutions purely because there is little regulation oversight… if you want a gradual increase in pH, GH and KH.. add stones..a common one is limestone (you can even buy pebbles and put it in the filter). However, many other stones can get the job done.. the only issue is.. what other metals could the stone be leaching?… I run an ICP test after two weeks to see… if it’s higher in heavy metals.. ditch the Rock and pick another or do frequent water changes.
If you’re in a time crunch, I would start mixing spring water to your treated water and test the chemistry.. chances are you’ll be somewhere in between.
Just a thought.

What is buffer capacity in this case then? The kh was already at 2 (20mg/L), would that not be providing a buffer as well?

Why did adding .21g of alkaline buffer and .11g of acid buffer raise the pH from 6.8 to 6.9 without touching kh,
But adding .45g of alkaline buffer and .20g of acid buffer the next day raised the pH from 6.9 to 7.4 and the kh from 2 to 10 (100mg/L)??

 

[chicco]

Because “acid buffer” and “alkaline buffer” are trade marked products. In chemistry you have electron donors or electron acceptors, this allows weak acids to donate protons or weak bases to accept protons. Buffers are usually weak acids or bases plus it’s salt form. GH and KH are measured in parts per million and represent alkaline earth metal ions and bicarbonate salt concentrations respectively. I have no idea what they use as “acid” or “base” buffer so I can’t tell you. I would go a more natural route purely because spring water usually has a wide variety of minerals in balanced proportions…. And if it’s too hard… dilute it.
just don’t use Arrowhead because when I ran an ICP I found arsenic among other toxic heavy metals.

 

[faebugz]

Because “acid buffer” and “alkaline buffer” are trade marked products. In chemistry you have electron donors or electron acceptors, this allows weak acids to donate protons or weak bases to accept protons. Buffers are usually weak acids or bases plus it’s salt form. GH and KH are measured in parts per million and represent alkaline earth metal ions and bicarbonate salt concentrations respectively. I have no idea what they use as “acid” or “base” buffer so I can’t tell you. I would go a more natural route purely because spring water usually has a wide variety of minerals in balanced proportions…. And if it’s too hard… dilute it.
just don’t use Arrowhead because when I ran an ICP I found arsenic among other toxic heavy metals.

Alkaline buffer is bicarbonates and carbonates. Acid buffer appears to be sulphate based, but I don't know exactly what is in it.

More strange happenings.. I checked Arthur's tank again today, 2 days later, after not doing anything at all to it the past few days besides checking it.

New parameters: ph 7.2/gh 3(60mg/L)/kh 5(50mg/L)

So to recap:

Sept. 06

- pH 6.9/gH 3/kh 2

-Addition of .45g alkaline buffer and .20g acid buffer

///

Sept. 07

-pH 7.4/gH 4/kh 10

///

Sept. 09

-ph 7.2/gH 3/kh 5

///

And strangely enough, I've tested my other axolotl tank and it has remained stable or done what was expected, despite using the buffers. So the problem isn't my water or the buffers inherently, it's something specific to Arthur's tank