Kalk maintaing Ca but not Alkalinity

[flying4fish]

Since I first started reefing I've used 2-part to maintain calcium and alkalinity levels. My pH was always low, and after quite a bit of searching the web I decided to try Kalk. A video on BRSTV made it sound like the best option. I've been trying it for about a week and I'm pleased with finally seeing pH levels over 8, and my Ca levels are being maintained nicely, but my alkalinity keeps dropping to the mid 7's every day. I add some BRS liquid soda ash and adjust my dosers to increase the amount of Kalk I'm adding. I have a Red Sea Reefer 170 and I'm currently adding 70ml of kalk/hour (1680 ml/day). I'm already using the max saturation of Kalk (2+ tsp/gallon RO water). I just increased my dosers to 80ml/hour, but is this ever going to balance out? And a quick search of this forum I found some threads from others that are maintaining there alkalinity but the calcium levels begin to go through the roof. It doesn't seem that using Kalk is as simple as the video on BRSTV led me to believe! Do most of you bring the Kalk dosing down to the level that maintains Ca, and then just supplement with liquid soda ash??

 

[Lasse]

but my alkalinity keeps dropping to the mid 7's every day

Is there a swing in KH depended on time you take your sample? If you take a sample 24 hours later (without doing anything else) will it show nearly the same as 24 hours earlier?

Sincerely Lasse

 

[Randy Holmes-Farley]

Limewater/kalkwasser delivers alk and calcium in a ratio that is actually a slight excess of calcium long term. But that effect is small and not noticeable on a day to day basis.

My Triton Testing Results: By Randy Holmes-Farley - REEFEDITION

Recently, Triton GmbH in Germany has initiated a method of testing many ions at once for a single price. In the US, that service is coordinated by Unique Corals. For $49 they will send you a couple of tubes to collect a tank water sample, and a prepaid mailer to send the sample back to them...

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Calcium (Ca). In my reef aquarium, I use only Instant Ocean salt and I have not added any additional calcium except as limewater for a number of years (during which time I have continued regular 1% daily water changes). So why is my calcium level (472 mg/L) higher than one would normally expect for Instant Ocean (maybe between 350 and 400 mg/L)? That long term rise in calcium is actually the expected result when using limewater to maintain alkalinity.

Limewater adds calcium and alkalinity in exactly the same proportions as in pure calcium carbonate. So if that is what is used by corals to make skeletons, and what precipitates on pumps and such, then calcium would stay constant.

But both magnesium and strontium get into growing calcium carbonate crystals in place of some of the calcium. A few percent of the calcium is replaced this way. Consequently, since the same amount of alkalinity (the carbonate) is used over time, and somewhat less than the balancing amount of calcium, calcium rises if alkalinity is maintained. I’m happy to see the result match the theory, and the calcium level seems fine to me.

 

[flying4fish]

Is there a swing in KH depended on time you take your sample? If you take a sample 24 hours later (without doing anything else) will it show nearly the same as 24 hours earlier?

Sincerely Lasse

I have only checked at 24 and 48 hour intervals (not anything less). If I wait 48 hours, the KH deficiency is about 2X that compared to a 24 hour interval. Does that answer your question?

 

[Randy Holmes-Farley]

I have only checked at 24 and 48 hour intervals (not anything less). If I wait 48 hours, the KH deficiency is about 2X that compared to a 24 hour interval. Does that answer your question?

can you give an example in dKH and ppm?

 

[flying4fish]

can you give an example in dKH and ppm?

Indeed I can. On 22 March 132 ppm (7.4 dKH); I adjusted back up to 9dKH. On 23 March 134ppm (7.5dKH). And I just checked again now, about 20 hours after my last check, and found 123ppm (7.1dKH). One thing I just noticed, my Hannah reagent is a few months out of date. I'm not sure if that might be a factor. I just ordered new stock.

 

[Lasse]

One thing I just noticed, my Hannah reagent is a few months out of date. I'm not sure if that might be a factor. I just ordered new stock.

Please see this

Important findings according how to store open bottles of the reagent for Hanna Marine alkalinity checkers

There is a way to hinder the Hanna alk to show lesser and lesser dKH (or ppm for that matter) with age of open reagent bottle. I had the same story as many have reported here - my reading decrease from a new open bottle with time. Double check with another method show that there was not a real...

www.reef2reef.com

It seems that you have a lot of CaCO3 consumption in your tank. However - the consumption is not equal during 24 hours. IME - around 70 % of the calcification take place from around 3 hours after light switch on to around 2-3 hours after it switch of. A daily alkalinity swing around 0.3 to 0.6 dKH is not uncommon in such heavy "planted" reef aquarium IME. But it looks that you lose alkalinity over time.

Sincerely Lasse

 

[flying4fish]

Thanks so much, Lasse. Clearly I can't make any conclusions until I get a new bottle of reagent! I live on the Big Island so I can't get any locally...but I'm having some expressed to me. In the meantime I'm not going to add anymore soda ash, I'll just let the Kalk do it's thing until I get the new test kit. For all I know I could have dKH super high already. I'll do a partial water change today.

 

[Lasse]

I use the same checker as you and it works well since I start with storing the reagent in the refrigerator. However - I have always a normal titration test (like Tropical Marine Pro test) so I can get a second option if I be unsure.

Siuncerely Lasse

 

[gbroadbridge]

Indeed I can. On 22 March 132 ppm (7.4 dKH); I adjusted back up to 9dKH. On 23 March 134ppm (7.5dKH). And I just checked again now, about 20 hours after my last check, and found 123ppm (7.1dKH). One thing I just noticed, my Hannah reagent is a few months out of date. I'm not sure if that might be a factor. I just ordered new stock.

How did you adjust back to 9dKh?

Did you measure Alk ikmmediately after your adjustment?

 

[thatmanMIKEson]

I use the same checker as you and it works well since I start with storing the reagent in the refrigerator. However - I have always a normal titration test (like Tropical Marine Pro test) so I can get a second option if I be unsure.

Siuncerely Lasse

Is keeping it in the refrigerator recommended? No worries about condensation when it is out for testing? Condensation in the reagent bottle, and the covett getting Condensation on the outside, causing interference with the testing.. I go thru it quick but I still get the golden crusties on the cap if I lay it down so now I make sure to leave it sitting up right until its gone.

 

[Lasse]

Apparently - Hanna do not recommend refrigerator - see here . But my problem disappear when I start to store it in the refrigerator. I hope that people that start to do what i do will comeback in the original thread with their findings and we will find out in the long run if it was "once in a lifetime" with my experiences or not. Condensation on the outside in a sample of 10 ml - I do not think it has any importance and I always wipe the tip dry before adding any reagents into the sample.

Sincerely Lasse

 

[Subonidio]

Since I first started reefing I've used 2-part to maintain calcium and alkalinity levels. My pH was always low, and after quite a bit of searching the web I decided to try Kalk. A video on BRSTV made it sound like the best option. I've been trying it for about a week and I'm pleased with finally seeing pH levels over 8, and my Ca levels are being maintained nicely, but my alkalinity keeps dropping to the mid 7's every day. I add some BRS liquid soda ash and adjust my dosers to increase the amount of Kalk I'm adding. I have a Red Sea Reefer 170 and I'm currently adding 70ml of kalk/hour (1680 ml/day). I'm already using the max saturation of Kalk (2+ tsp/gallon RO water). I just increased my dosers to 80ml/hour, but is this ever going to balance out? And a quick search of this forum I found some threads from others that are maintaining there alkalinity but the calcium levels begin to go through the roof. It doesn't seem that using Kalk is as simple as the video on BRSTV led me to believe! Do most of you bring the Kalk dosing down to the level that maintains Ca, and then just supplement with liquid soda ash??

Hi

If your Tank stays at 7ish you are good

I have a Kalk reactor and I stay at 7ish sometimes I drop to 6.5

And my. Corals look great SPS Dominated coloration looks better at lower alkalinity (Sea levels are at 7. )

Don't chase a number you are going to drive your self crazy

If you want to keep it higher for growth acceleration, then you can dose ALK in a control manner , checking your readings every day at the same time...... but I would not chase a number

 

[Subonidio]

 

[Subonidio]

Always ask for pictures .....it's a lot of reefers that like to Talk but their Tanks look sad

 

[Subonidio]

 

[Subonidio]

I have to frag often because they grow so fast

 

[tapeworm123]

I have the same problem and have for a few tanks now. I’m not sure if hanna alk checker has a problem testing the kind of alk that kalk produces or something is wrong. I have a lightly stocked 40 gallon breeder now and still the same problem. I upped the kalk and no change except the alk is dropping faster like it is only adding in calcium.

 

[Subonidio]

Yeah I noticed that I have to keep Mag high .... since I started using my Kalkwaser stirer

 

[Randy Holmes-Farley]

The simple explanation is that kalkwasser is not perfectly balanced, as it adds a bit more calcium than alk in relation to consumption.