Kalkwasser pH dropping

[five.five-six]

A few things to get out of the way:

The pH probe is 6 months old

I calibrated it Wed, the 6th and to rule out bad calibration fluid, I bought new pinpoint fluid and calibrated again Saturday.

Yesterday I cleaned out my Kalkwaser reactor and added about 1/2 pound of calcium hydroxide to it. Today I see the internal pH dropping at an alarming rate.

What could be causing this? I evaporate less than 2 gallons a day

According to this calculator, that should last 30 days. 1 pound of calcium hydroxide should fully saturate about 50 gallons of water. I’ve run 2 gallons through and the pH is already falling. What gives?

https://www.avastmarine.com/pages/kalkulator

 

[joseserrano]

Maybe kalk is bad or exposed to air/got wet

 

[pledosophy]

How are you storing your kalk between use?

I keep mine in an airtight bag, and that bag is in an airtight food safe bin. Even exposure to air will lower the pH. You end up needing 2-10x as much for the same results.

Also I thought I was the last person alive to have that CA Reactor. Glad yours is still going strong.

 

[five.five-six]

How are you storing your kalk between use?

I keep mine in an airtight bag, and that bag is in an airtight food safe bin. Even exposure to air will lower the pH. You end up needing 2-10x as much for the same results.

Also I thought I was the last person alive to have that CA Reactor. Glad yours is still going strong.

I keep it sealed in a 5 gallon bucket with a screw on top and a rubber O-ring. I transfer it as needed into a 1 gallon bucket with an O-ring lid and use it from the 1 gal bucket to limit air contamination from the main supply.

The pH has actually dropped .1 since I opened this thread. Whisky Tango Foxtrot?

The only thing I can think os that I know my RO membrane is smoked, waiting for a replacement from spectrapure but I did put fresh DI in my polishing stage.

RO output is 72 PPM
DI output is 0 PPM

It’s not great but I don’t see how that can cause my Kalk to lose potency that fast.




As for using kalkwasser, it can be messy and requires effort and a bit dangerous but it’s really a hidden gem. It helps with pH, super purifies water, adds a balanced ratio of anlkalinity and calcium, and it’s relatively inexpensive.


Back in the day, we would ATO with tap water mixed with calcium hydroxide and just make sure the pickup tube stayed 1/2“ off the bottom of the container because the kalkwasser would condensate all the impurities and they would sink to the bottom. I setup systems with a flexible PU hose that would float 1/2” below the top of the kalkwasser but a stopper so it would start drawing air when there was 1/2” left at the bottom. These reactors really simplify the process.

 

[five.five-six]

Maybe kalk is bad or exposed to air/got wet

I don’t think so. I keep the big bucket sealed tight. The old IO bucket that you have to hit with a hammer to open and close. The smaller bucket has a snap lid but it’s has an O-ring too.

I split a 50# bag with @laverda but we haven’t opened that yet. I‘ve emptied the 5 gal bucket and it’s time to split that bag, see if that makes a difference.

 

[pledosophy]

I would put that bucket in a bag. Just what I would do.

 

[Coloredrock]

Rule out the kalk powder... when I open it out of the container I put it in to separate zip lock bags and remove all the air from the bags. DEA would be like WTF?

 

[DEWreefing]

I wouldn't worry about .2 drop most likely do to extra CO2 in the house being summer windows not open. Did the tanks ph drop the same?

 

[Ohiostreetz]

Easy enough to just check the PH of the solution if it’s lower than the tank PH then something is wrong with the Kalk. Atleast that would answer the question about if it’s the Kalk slurry doing it

 

[five.five-six]

I wouldn't worry about .2 drop most likely do to extra CO2 in the house being summer windows not open. Did the tanks ph drop the same?

There abouts.

 

[pledosophy]

I wouldn't worry about .2 drop most likely do to extra CO2 in the house being summer windows not open. Did the tanks ph drop the same?

pH is calculated in powers of ten. A .2 drop would need to be compensated for to achieve the same result IME For a .2 drop you might need to increase dosing 20%, maybe more. It really does make a huge difference.

 

[DEWreefing]

Mark have you checked the discharge tube and cleaned it out they do get clogged.

 

[Sold4JC]

Is your house running warmer? Kalk has different PH based on the temperature. The lower the temperature, the higher the Ph. I moved my reactor out of my sump because I got a better reactor Ph with colder water.

 

[five.five-six]

Is your house running warmer? Kalk has different PH based on the temperature. The lower the temperature, the higher the Ph. I moved my reactor out of my sump because I got a better reactor Ph with colder water.

yea, house is warmer... I don't know if that accounts for it though. I did get 25#'s of new kalk. the stuff I'm using for the last 2 years had been stored in that bucket 15 years prior.

 

[five.five-six]

Mark have you checked the discharge tube and cleaned it out they do get clogged.

Yea, I've noticed .... so has my wife and she takes the opportunity to affirm her undying love for me and my fu***ng fishtank...