Old Kalk

[ptrusk]

I have a 4# tub of ESV Kalk. At least 10 years old. Container has been open that long. Is the potency affected?

I have a couple tanks I'm tired of dosing 2 part manually so I am going to use kalk in top off. I set up salt buckets with kalk for ATO. Pretty sure it will eat them and make them crack. What is a good 5 or so gallon container (cheap) that is kalk resistant?

 

[Randy Holmes-Farley]

It may have absorbed significant CO2, forming calcium carbonate.

You can likely still use it if you are ok with lots of solids on the bottom and have a way to measure potency, such as conductivity.

 

[ptrusk]

Thank you sir. I don't have a conductivity meter but I used a pool pH test strip and it says 12.5 pH so I think It still has some kick.

 

[Randy Holmes-Farley]

Thank you sir. I don't have a conductivity meter but I used a pool pH test strip and it says 12.5 pH so I think It still has some kick.

Just bear in mind the lack of precision with such a test, and a difference of 0.3 pH units is a drop in potency of a factor of 2.

 

[X-37B]

Kalk is cheap. Why bother with 10 year old stuff if you have no way to test it.
I use an acrylic tank to dose mine and have used a 5g bucket before with no issues.

 

[BryanM]

Agreed with the above, its not expensive, personally I'd replace it.