Kalkwasser issues

Geoology · Apr 24, 2022

I believe that is what happened. I went yesterday and bought new kalkwasser (although the only one they had was seachem which was super expensive). Put it in the stirrer and now seems back to what it was. Thanks for all the responses.

Randy,
I also purchased a TDS meter to be able to keep better track of saturation. When I was looking through posts before I saw what that tds number should be. I cannot find that now. What should my tds be in the stirrer for max saturation?

atoll · Apr 24, 2022

Geoology said:
I believe that is what happened. I went yesterday and bought new kalkwasser (although the only one they had was seachem which was super expensive). Put it in the stirrer and now seems back to what it was. Thanks for all the responses.

Randy,
I also purchased a TDS meter to be able to keep better track of saturation. When I was looking through posts before I saw what that tds number should be. I cannot find that now. What should my tds be in the stirrer for max saturation?

TDS or PH?

Garf · Apr 24, 2022

I would have thought the kalk should still saturate the solution and leave the calcium carbonate in the undissolved portion of the stirrer though.

Geoology · Apr 24, 2022

atoll said:
TDS or PH?

tds

atoll · Apr 24, 2022

Geoology said:
tds

Now am confused as most use a PH meter to determine how well kalk is doing as the PH will drop when spent. Not sure how you use a TDS meter to determine kalk. But would like to know more.

BTW. I would consider buying your kalk from a reputable scientific chemical supplier as you will get the same thing (minus the pretty coral on the tube which we all know makes it worth 10X as much) but for much better value and the same if not better quality.

Geoology · Apr 24, 2022

Randy-Holmes talks about it in a couple of posts I believe he said he thinks that TDS is a better indication of saturation. (Sorry if I miss quoted). I just cant seem to find were it is now.

Dennis Cartier · Apr 24, 2022

The benefit of using EC (TDS) is that the reading declines in a linear fashion with the saturation. Fully saturated is 10.3 mS, so 50% saturation is 5.15 mS.

When using pH, a tiny decrease in pH amounts to huge declines in saturation to the point where using pH does not make sense for monitoring saturation.

On the speed of kalk degrades when exposed to air. I found the zipper on my 8 lb bag of kalk had failed to close properly a couple of times. I have placed the bag in an old salt bucket with a tight fitting lid to avoid this in the future, but since then my saturation is between 80 and 90% when adding fresh kalk from that bag.

Geoology · Apr 24, 2022

Dennis Cartier said:
The benefit of using EC (TDS) is that the reading declines in a linear fashion with the saturation. Fully saturated is 10.3 mS, so 50% saturation is 5.15 mS.

When using pH, a tiny decrease in pH amounts to huge declines in saturation to the point where using pH does not make sense for monitoring saturation.

On the speed of kalk degrades when exposed to air. I found the zipper on my 8 lb bag of kalk had failed to close properly a couple of times. I have placed the bag in an old salt bucket with a tight fitting lid to avoid this in the future, but since then my saturation is between 80 and 90% when adding fresh kalk from that bag.

Maybe it is just that I bought the wrong TDS meter. The one I have is PPM. When you say 10.3 mS is that 10.3mS/cm or 10.3mS/m as the conversion dosn't seem right as I am getting about 500 ppm. Can I use this TDS meter or do I need to get one that measures mS

Dennis Cartier · Apr 24, 2022

No, you can use it. TDS is just a calculation based on electrical conductivity. The fully saturated reading is 10.3 ms/cm, which would be about 515 ppm TDS if your meter is using a conversion factor of ec/2, which is often the case.

So if you are getting 500 ppm, that is about 10 mS, so pretty close to 10.3 mS and may just be calibration.

Geoology · Apr 24, 2022

Dennis Cartier said:
No, you can use it. TDS is just a calculation based on electrical conductivity. The fully saturated reading is 10.3 ms/cm, which would be about 515 ppm TDS if your meter is using a conversion factor of ec/2, which is often the case.

So if you are getting 500 ppm, that is about 10 mS, so pretty close to 10.3 mS and may just be calibration.

Hanna's website says ec to tds is 0.5. So that seems correct I believe.

Thanks

Randy Holmes-Farley · Apr 24, 2022

Geoology said:
I believe that is what happened. I went yesterday and bought new kalkwasser (although the only one they had was seachem which was super expensive). Put it in the stirrer and now seems back to what it was. Thanks for all the responses.

Randy,
I also purchased a TDS meter to be able to keep better track of saturation. When I was looking through posts before I saw what that tds number should be. I cannot find that now. What should my tds be in the stirrer for max saturation?

You can easily determine what reading you get by outting the probe in truly saturated kalk. Say, 2 teaspoons calcium hydroxide slurries in 1 cup RO/di. It is about 10.3 mS/cm. What that reads in tds varies a bit based on the tds scale used.