Kalk amount in a PM KR620

[navychief]

Hi, Reefers

I own a Precision Marine KR620 Kalk reactor. The instructions that came with the reactor calls for mixing no more than 2 cups of pickling lime as a slurry and then pouring it into the reactor; I figured the reactor volume at 2.2 gal.

My question is I've read that one should mix about 2 teaspoons per gallon of RO/DI. So as you can see, that's a pretty wide range of lime. So with that being said, I'm only using 4 teaspoons of Mrs. Wages Pickling lime in my PM reactor.

Does this amount sound right? And if so, at what point should I recognize that I need to refresh the lime slurry to maintain potency?

Thanks,

Chief out.

[tmz]

Sorry Chief, I'm not familiar with your reactor . I use a still reservoir for dsoing it.

[navychief]

Thanks. The reactor isn’t as important as the amounts of lime. Me thinks...

[bertoni]

With a Kalk reactor, the idea is to put a lot of lime into it so that as water is added automatically, more Kalk will dissolve. Only two tsp of lime will dissolve per gallon of water, and the rest remains in the reactor. Over time, calcium carbonate will form in the reactor, which will look a lot like Kalk but won't dissolve.

The only way to be sure about the potency of the Kalkwasser is to measure it. You can do that with a pH meter, with a reasonable degree of accuracy, or get a conductivity meter that measures in the 10 mS/cm² range. You could get some estimate if you know the amount of water that has passed through the reactor. What equipment do you have for measuring pH?

[navychief]

Thanks, Jon. I forgot to consider the fact of passing newly created water through the lime mixture. This unlike a stable mixture of dripping a gallon only.

I have two Apex pH probes. One of which monitors the tank pH. The other pH probe was in my change water, but I determined it was pointless to keep using it since my mixture of new salt water was always at the pH as indicated in the mixing chart. I use RS Pro.

I have a handheld pH meter. I can most certainly use it.

[bertoni]

Okay, to get an idea of the saturation level, you will need to add ½ tsp or so of Kalk to create a saturated solution. That'll be your reference solution. Once you measure the pH of the new Kalk solution, you can measure the output of your reactor. Each 0.3 units of pH difference between the two corresponds to a ½ decrease in concentration.

The pH of Kalk is high enough (12.54 at saturation) that your meter won't be able to measure it accurately, thus the need for the reference solution.

[navychief]

Originally Posted by bertoni

Okay, to get an idea of the saturation level, you will need to add ½ tsp or so of Kalk to create a saturated solution. That'll be your reference solution. Once you measure the pH of the new Kalk solution, you can measure the output of your reactor. Each 0.3 units of pH difference between the two corresponds to a ½ decrease in concentration.

The pH of Kalk is high enough (12.54 at saturation) that your meter won't be able to measure it accurately, thus the need for the reference solution.

So I measured my Kalk reactor. Reading was 12.4. Did the reference solution. It read 12.2. No real difference.

[bertoni]

Hopefully, that means your reactor is near full saturation. It's a little sad that the reference measures lower. That's probably a meter limitation. That level is rather high.

[navychief]

Originally Posted by bertoni

Hopefully, that means your reactor is near full saturation. It's a little sad that the reference measures lower. That's probably a meter limitation. That level is rather high.

Yeah. And that's only 4 tbsp. to 2.2 gals. Probably will not stay saturated long though.

[navychief]

Originally Posted by bertoni

Hopefully, that means your reactor is near full saturation. It's a little sad that the reference measures lower. That's probably a meter limitation. That level is rather high.

By the way. Thanks for the help.

[bertoni]

You're welcome. Good luck!