Kalkwasser not raising alk or ph

[Randy Holmes-Farley Verified Community Expert]

I’ve got a question that I’m frustrated with.
I’m dosing kalk and doing 2 tsp per gl of RODI.
I’m checking potency with an HM Digital 100 using mS. I calibrated the mS with HM Digital solution.
I use the brs 1gl space saver and dose 480ml a day and still need to supplement 2 part.
I found this thread and have made 4 different 1gl solutions, starting from scratch on each. 1st, 2 tsp of brs kalk
2nd, 3 tsb of kalk
3rd, 4 tsb of kalk
4th, 6 tsb of kalk… all are under 7.14mS. Each jumps up about 1.0mS

I did 2 different batches of 1 cup RODI & 2 tsp of kalk, I just mixed differently. One by hand for 30sec or so and the 2nd on a magnetic stirrer for 20min. Magnetic stirrer was 7.12mS and the 30 sec hand mix was about 5.2

How do I achieve 10+mS or 12+ PH per gl?

That meter maxes out at 9.99 mS/cm so will never read higher.

It sounds to me like your meter is just off and 7 mS/cm is saturation for you.

what temp are you doing this at? Kalk dissolves less and has lower conductivity at higher temps.

 

[West1]

That meter maxes out at 9.99 mS/cm so will never read higher.

It sounds to me like your meter is just off and 7 mS/cm is saturation for you.

what temp are you doing this at? Kalk dissolves less and has lower conductivity at higher temps.

Temp is between 70.5-71.5*

if 7mS is saturation for me, is there a way to bump it up or am I fighting a useless battle?

I do test display with a Milwaukee meter and my PH doesn’t move. When I first started dosing, it went up to 8.15. Lasted about 3 weeks.

I did not realize this meter doesn’t go high.
Can you recommend a decent meter at a reasonable price?

 

[arking_mark]

That meter maxes out at 9.99 mS/cm so will never read higher.

It sounds to me like your meter is just off and 7 mS/cm is saturation for you.

what temp are you doing this at? Kalk dissolves less and has lower conductivity at higher temps.

Mine maxes out there as well...very frustrating.

 

[Randy Holmes-Farley Verified Community Expert]

Temp is between 70.5-71.5*

if 7mS is saturation for me, is there a way to bump it up or am I fighting a useless battle?

I do test display with a Milwaukee meter and my PH doesn’t move. When I first started dosing, it went up to 8.15. Lasted about 3 weeks.

I did not realize this meter doesn’t go high.
Can you recommend a decent meter at a reasonable price?

I mean the 7 you read may be a real 10 mS/cm.

 

[West1]

I mean the 7 you read may be a real 10 mS/cm.

I see what your saying. By testing the kalk in 1 cup of water and getting similar number could be my meter is off.
Thank you Randy!

 

[Justdrew]

I’ve got a question that I’m frustrated with.
I’m dosing kalk and doing 2 tsp per gl of RODI.
I’m checking potency with an HM Digital 100 using mS. I calibrated the mS with HM Digital solution.
I use the brs 1gl space saver and dose 480ml a day and still need to supplement 2 part.
I found this thread and have made 4 different 1gl solutions, starting from scratch on each. 1st, 2 tsp of brs kalk
2nd, 3 tsb of kalk
3rd, 4 tsb of kalk
4th, 6 tsb of kalk… all are under 7.14mS. Each jumps up about 1.0mS

I did 2 different batches of 1 cup RODI & 2 tsp of kalk, I just mixed differently. One by hand for 30sec or so and the 2nd on a magnetic stirrer for 20min. Magnetic stirrer was 7.12mS and the 30 sec hand mix was about 5.2

How do I achieve 10+mS or 12+ PH per gl?

Just curious what size the tank is and how much evaporation? I have a 40B and I am 1700ml a day for kalk. 480ml is not that much.

 

[West1]

Just curious what size the tank is and how much evaporation? I have a 40B and I am 1700ml a day for kalk. 480ml is not that much.

Reefer 525xl, I believe 139 total glns.
I’m guessing I’m about 2glns evaporation per day with current kalk dosing. I need to refill a 15gl DI reservoir every week.

Wow, 1700ml per day is a lot! My tank has a lot of frags, nothing big enough to be called a colony.

 

[Justdrew]

Reefer 525xl, I believe 139 total glns.
I’m guessing I’m about 2glns evaporation per day with current kalk dosing. I need to refill a 15gl DI reservoir every week.

Wow, 1700ml per day is a lot! My tank has a lot of frags, nothing big enough to be called a colony.

I have a lot of SPS frags, but a huge hammer and duncan. You have room to add a lot more kalk with your evap.

 

[Justdrew]

In 139 gallon water volume 480ml only raises ALK by .105 per day. Most tanks even with frags will consume more than that.

 

[West1]

In 139 gallon water volume 480ml only raises ALK by .105 per day. Most tanks even with frags will consume more than that.

Thank you. I’m fairly new at understanding the depth of kalk.

is this a good meter, it’s 0-20.00mS

Gro’Chek EC/TDS and Temperature Monitor (High Range) - HI993302

 

[Randy Holmes-Farley Verified Community Expert]

I see what your saying. By testing the kalk in 1 cup of water and getting similar number could be my meter is off.
Thank you Randy!

Yes, and there’s no need for a meter reading above 9.99 mS/cm because that is very close to true saturation.

if possible, you might even try to recalibrate the device to read 9.98 in true saturated kalkwasser. If not, just assume 7 is saturated..

 

[jduong916]

Yes, and there’s no need for a meter reading above 9.99 mS/cm because that is very close to true saturation.

if possible, you might even try to recalibrate the device to read 9.98 in true saturated kalkwasser. If not, just assume 7 is saturated..

Can you use a tds meter that goes from 0-9999 tds? Ive see two equations to convert though. Ec*.5 = tds. There was also ec*.7 = tds. Which is right? I guess fully saturated lime water would have a tds 5150 ppm or 7210 ppm.

 

[Oregon Grown Reef]

How long to stir is a bit of guesswork when not monitoring conductivity since it depends on particle size, turbulence, etc.

Overnight is plenty. A few minutes might be enough. When I was mixing, 15-30 minutes got most of the way there.

15-30 minutes? Would mixing for like 2 minutes not be enough? If that's the case, I'm not mixing for nearly long enough as I was concerned about co2 getting into the solution if I mixed it for too long.

 

[Randy Holmes-Farley Verified Community Expert]

Can you use a tds meter that goes from 0-9999 tds? Ive see two equations to convert though. Ec*.5 = tds. There was also ec*.7 = tds. Which is right? I guess fully saturated lime water would have a tds 5150 ppm or 7210 ppm.

There are different tds scales to convert tds to mS/cm.

I’d just try it in truly saturated limewater to see.

 

[Randy Holmes-Farley Verified Community Expert]

15-30 minutes? Would mixing for like 2 minutes not be enough? If that's the case, I'm not mixing for nearly long enough as I was concerned about co2 getting into the solution if I mixed it for too long.

In my Brute it took that long.

 

[Oregon Grown Reef]

In my Brute it took that long.

Ah. Makes sense. My 5 gallon bucket mixes much faster by hand. Good to know.

 

[jduong916]

There are different tds scales to convert tds to mS/cm.

I’d just try it in truly saturated limewater to see.

So if i just get a cup and put a tbs of kalk in. Then measure the tds, i could use that value for my large vat of kalk. Does that sound right?

Not to highjack the thread, but i posted this yesterday and it wasnt in the chemistry forum. I turn my calc rx off. The pumps, doser, and co2. Is it ok for me to just leave the media in the chamber if the ph is 6.7? I plan to leave it like that for a couple months, but i dont know if the media will dissolve if it just sits there in 6.7 ph.

 

[Randy Holmes-Farley Verified Community Expert]

So if i just get a cup and put a tbs of kalk in. Then measure the tds, i could use that value for my large vat of kalk. Does that sound right?

Not to highjack the thread, but i posted this yesterday and it wasnt in the chemistry forum. I turn my calc rx off. The pumps, doser, and co2. Is it ok for me to just leave the media in the chamber if the ph is 6.7? I plan to leave it like that for a couple months, but i dont know if the media will dissolve if it just sits there in 6.7 ph.

Only a little will dissolve, but I’d personally drain it to avoid it becoming anaerobic.

yes, let’s see what the cup of RO/do with a tablespoon of calcium hydroxide in it reads after my mixing a bit. If it is maxed out, the test is a fail, but a normal reading can be used to gauge potency.

 

[jduong916]

Only a little will dissolve, but I’d personally drain it to avoid it becoming anaerobic.

yes, let’s see what the cup of RO/do with a tablespoon of calcium hydroxide in it reads after my mixing a bit. If it is maxed out, the test is a fail, but a normal reading can be used to gauge potency.

Could I leave the dosing pump on to move water through the reactor? I really don’t want to drain it.

 

[Randy Holmes-Farley Verified Community Expert]

Could I leave the dosing pump on to move water through the reactor? I really don’t want to drain it.

Why not? Can’t you just disconnect a hose and drain it?

Short of that, I’d just shut off the CO2 and leave everything else as normal.