Kalk... What has happened to the good old white powder?

I use Brightwell kalk 2+ and it buffers my Sr nicely and no issues , I have decreased my dosing manually of it since using Brightwell.
 
I used a kalk stirrer.
Old school, Reeftek KR200. Add slake lime, 3 to 4 heaped teaspoons in it per week. Connected to my auto top up.

But you need to ensure that the top up time is short, so your low and high float valves needs to be very close to each other. You do not want to blow the kalk out of the chamber, only the saturated water at the top.

but I disconnected it a year ago. Was away too much to be able to refill it weekly, and did not bother the tank sitter with it either.

with it in place my PH stayed at 8.0 to 8.1. Without my PH swing from 7.7 to 8.0.

PH swing is not bad, as long as it is the same swing every day. but lately it is dropping at times in the morning to 7.6. Need to put it back in action.
 
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Thanks @NO3 for the compliment, but as Carlos said, I am not the only one with valuable input….. @Midnight Reefer, corrected my answer, regarding the sir part, I think we’ll leave that for those who wears ties and or have beards……
Would love for SIR @Nemos Janitor to elaborate on the brittle skeletons and especially the skeletal breathing issues suspected…… The documentation is out there.
Not going to ramble too much about kalkwasser, there is way to much information on good old google….
ust to elaborate a bit for the newbies (as mentioned, there seems to be a lack of understanding / knowledge of this potentially wonderful / deadly white powder).
Essentially what Kalkwasser is, is a solution of Calcium Hydroxide in water(usually RO), with an extremely high pH, used by aquarists to increase pH, and add Calcium and alkalinity in a balanced (i.o.w. as used in calcification) fashion. Further benefits include precipitation of metals such as copper PO4 and other harmful substances.
The powder is not very soluble in fresh water, and only about half a teaspoon will dissolve in fresh water, yielding a pH close to 12!!! Yes, this stuff is caustic and aquarists should wear protective clothes and not breathe in the powder…..
An overdose in your tank will increase pH and will most likely wipe out most, if not all, of your livestock….. Sounds scary……
That being said, it is still a very useful way of supplementing alkalinity and calcium, raising pH and doing its bit to make PO4 les available to nuisance algae.
The most important thing to note with kalkwasser addition is simply to do it slowly, No more than ½ liter per hour of saturated kalk per 200 litres of tank volume is what I would consider the max or, when using the slurry method (google it) to do so cautiously and use a pH pen!
I use it in my top up reservoir as follows, simply judge the amount of water I added to my reservoir, and add two tsp per litre of kalk powder, stir and let it settle. I add more than needed, due to the nature of kalk to react with CO2 in the water and precipitate in the useless form of calciumcarbonate. To avoid excessive amounts being added by my atu, I have the following fail safes in place:
I turn off the atu for a few hours after mixing in kalk powder. This gives the solution time to settle nd avoids addition of undissolved powder to the aquarium.
My atu is on a timer, 15min on and 30 min off.
A tap on the airline coming from my atu ensures a slow drip rate.
As great a supplement as this powder is, it is important to also remember the following:
It does not add a lot of calcium and alkalinity, so in a tank with heavy calcification rates (read sps dominated) it is unlikely to keep up with demand. There are ways to increase its effectiveness such as increasing evaporation rates and adding vinegar to the solution( 3ml per litre)…. Again, google it.
Kalkwasser does help a great deal with biologically available Ca and Alk, which encourages calcification, yet it does not add Mg and Sr, and a system solely reliant on kalkwasser will eventually become depleted in other elements taken up by calcification. Perhaps this is what SIR @Nemos Janitor was pointing towards?
Regarding the addition of SR an Mg in Kalkwasser, another post shortly.
 
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Something wrong there, maybe? My pH stays very stable. I have a probe to measure and a graph to over time to inspect it.

You have a massive tank volume @carlosdeandrade.... I'm only referring to using kalkwasser on pico / nano tanks.
On a larger tank, I agree, there wont be any pH swing... But smaller tank... Massive swing. Ive measured pH spike of up to 9.4 on my reef angel portal graph in my pico tank...
 
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on a pico tank your ATU should run for a few seconds each time it kicks in. The float valves should be very close to each other. So that the volume of new RO added each time the ATU runs, is a very low percentage. The ATU can rather run 3 times an hour, than once an hour.

Evaporation rate would be the same expressed in percentage for a 1000L system and a 50L system in the same room. Only variable would be total surface area. Lets ignore that for now.

On a big 1000L system, adding 1L RO each time the ATU runs, will not affect salinity or anything else. Well soo low that I doubt anybody got a piece of equipment that would show the difference, being 0.1%. But adding 1L RO in a 50L system, at 2%, and you are impacting salinity.

Now add white powder to the RO water. And the impact on PH will be more.

for the 50L nano to have the same 0.1% impact on the water parameters as the 1000L system. Each time the ATU run, it should add only 50ml RO. Then we are comparing apples with apples.

1L RO into a 1000L system, is the same impact as 50ml RO into a 50L system.

I doubt anybody ATU on the nano tanks adds just 50ml at a time.
 
Ok, just to let you know that Ivan (and I mean NO disrespect), is not the only "guru" on this forum. There are many, not mentioned or contributed to this thread, that have years of knowledge and experience and have some SOLID input. All you need to do is ask specific questions for specific answers.

LOL
 
@NO3, I was always using the kalkwasser in a reactor with my ATO, so not really possible to "lower" kalk levels.

Have you ever tested ph in your tank after adding kalk... It literally skyrockets for about an hour afterwards.

No i have a PH probe so i can just watch it !

Maybe i have a solution ................. T off your pipe before it gets to the reactor that way you can determine how much saturated ro water vs unsaturated ro can be added jut a thought!
 
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In no way is this intended to start an argument re a product, but I have mined some data regarding availability of Mg and Sr in Kalk:


Went to have a look at what the real gurus have to say:

adding lime in the form of limewater
This action causes calcium carbonate to precipitate due to exceeding the solubility product. Additionally, magnesium can be precipitated as magnesium hydroxide in a double displacement reaction.
http://en.wikipedia.org/wiki/Lime_softening

THE
SOLUBILITY OF CALCIUM CARBONATE AND OF

MAGNESIUM HYDROXIDE AND THE
PRECIPITATION

OF THESE SALTS WITH
LIME WATER.

GEORGE C. WHIPPLE AND ANDREW MAYER, JR.


It is
certain, however, that all modifications of

basic magnesium
carbonate are much more soluble than magnesium
hydroxide,
and in water softening, sufficient lime water is added to

precipitate all the magnesium in the latter form, i. e., as MgO2H2.......

......
Mag
nesium

hydroxide
is a colloidal precipitate, which requires a long time

to
settle, and tends to pass through filter paper. Therefore the

results
may be somewhat in excess of the true value.....

....
The solubility of magnesium hydrate, as determined by direct
experiment, was found to be 12 parts per million. By the precipitation
experiments
with lime it was found to be IO parts per million,

which
is probably more nearly correct, and which may be taken as

the most probable value.


http://www.advancedaquarist.com/2003/5/chemistry :

Sollubility of Me6als at H of 12.4:

Magnesium > 0.001ppm.

http://www.advancedaquarist.com/2003/12/chemistry

Aquarium Chemistry: Magnesium And Strontium In Limewater
By Randy Holmes-Farley, Ph.D. :

It is interesting to note that relative to calcium, magnesium is greatly underrepresented compared to that in the starting quicklime. The reason for this result is the well known insolubility of magnesium hydroxide. Any magnesium ions released into the solution rapidly combine with hydroxide to form insoluble magnesium hydroxide that precipitates.

http://archive.reefcentral.com/forums/archive/index.php/t-649826.html :

BUT if the two compounds (Calcium and Magnesium Hydroxide) are mixed together BEFORE having a full strenght calcium hydroxide saturated KW, THEN, some magnesium would stay into it. Does his theory make any sense, not chemically, but aquarium wise?

If you are talking about dissolving the magnesium, then no, it does not make sense unless the limewater is very, very dilute. Say, 1 teaspoon in 50 gallons of fresh water. I didn't show the graph in that article, but in this article I show the solubility of magnesium as a function of pH, regardless of the order of mixing.

Also, you told me strontium can be added to KW, so this is an option to dose it into our tanks, but, given the two options, isn't anyway better to dose Strontium in the old fashioned way of putting a few drops of a commercial/homemade supplement directly into the sump or in the flow of a pump once a week?

I don't dose strontium at all (water changes keep it up in my tank), but either way is fine if you choose to do so. :)


The Self Purification of Limewater (Kalkwasser)
302 Found

At pH values above 10.5, the magnesium concentration is very low. Saturated limewater is about pH 12.5. Half saturated limewater has a pH still above 12. At those values, the solubility of magnesium is far below 1 ppm.

http://www.reefcentral.com/forums/showthread.php?t=1290080 :

Bertoni's Comment: Hydroxides of calcium, magnesium and strontium. I don't see how the magnesium would work all that well. I suppose if the solution was stirred and the magnesium pumped into the tank as a precipitate, it might then dissolve. Sounds messy, though.

And Randy's Comment:
It won't work.

Here's my comment on kalk+2 from another thread:

Unfortunately, it is a very poorly designed product that won't work. It has very little magnesium in it, but even that will precipitate out in limewater as magnesium hydroxide.

Really, this is a pitiful product. Not enough magnesium to be useful even if it worked, and it won't work.

It is a marketing gimmick.

I show in the article linked below that bulk supplied calcium oxide and hydroxide have that amount of magnesium or more already in it.

I can do this all day, in fact, there is a lot more mining to do...
 
interesting :)
 
@irie ivan Hats off to you. That's the kind of answer I would expect from someone who knows what theyre saying. I think a conclusion has been reached, kalk+2 is 'kalk+2', it's not the good old fashioned kalk. If I had some, I wouldn't use it the same way I use kalk.

Strontium overdosing just scares the shit out of me anyways. As I understand it's toxic above 8ppm?

So the Mg content in brightwell's product is low for the reasons you just summed up, its so little it's meaningless almost. Sounds like calcium hydroxide with some Sr and a spit of Mg hydroxides, that you pay more for.....the hydroxides are probably more expensive than the opposing chloride salts?

I dunno what the cost of kalk+2 is per kilo but after this conclusion, I don't even care. I see it now as a company trying to make a awesome and time-tested thing better with a bit of 'fairy dust'. Which I think they have had a jolly good smash at! But wasting money is not on my agenda thank you :)
 
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Ok, So effectively, How much Calcium are we able to add per day with Kalkwasser as a top up replacement?
 
http://www.advancedaquarist.com/2003/11/chemistry
There have been relatively few studies on the toxicity of elevated strontium to most marine organisms. In most studies, researchers have found strontium to not be very toxic at levels that might be attained in a reef aquarium. In one study, researchers looked at developing mussel embryos ( Mytilus californianus ) for effects from barium and strontium. For strontium, they concluded that there were no effects at environmentally relevant levels, although barium was quite toxic at even fairly low levels......
......The most sensitive organism in table 3 appears to be a crab, with 38 ppm strontium reported to be lethal. If that experiment is valid, then aquarists would be cautioned to keep strontium from rising much above natural levels.

And to justify the agree for Dallas:

Kinetics of strontium uptake in the scleractinian coral Stylophora pistillata
Christine Ferrier-Pagès1,*, Florence Boisson3, Denis Allemand1,2, Eric Tambutté1

The incorporation of Sr2+ versus external Sr2+ concentration was also linear up to 3.42 mM (i.e. a concentration 37.5 times higher than normal seawater concentration). However, the uptake of Sr2+ at high concentrations (>1 mM) decreased with an increase in Ca2+ concentration in the seawater. Moreover, Verapamil, a Ca2+ channel inhibitor, also inhibits the incorporation of Sr2+ with the same Ic50 (12 µM) as for Ca2+. Incorporation of Sr2+ is therefore inversely correlated to the rate of calcification, suggesting interactions between these 2 ions, which should be taken into account during paleoclimatic studies.
 
BUT, what interests me more, is my previous post....

Have started with some legwork, my mathematical skills suck at the best of times, so can the clever people please assist.

Made a fresh saturated mix of kalkwasser yesterday, by mixing 2 tsp of PK kalk (an LFS in CPT home brand) in a litre of cold RODI water. I allowed it to settle fro a few hours, then diluted with RODI to minimize high pH interference with precipitation of Mg during testing.

Measured with a Red Sea pro test and a Salifert, both concurred at 400ppm after the dilution factor was reconverted to actual ppm.
I must add, there is no assay available on the product, very bad instructions and when opening it the colur had me very suspicious of the quality.

Unfortunately, my pH electrode is beyond its last measurememt, so once I have a replacement, I'll do some thorough brand testing....

Now for the math:

in a litre of kalkwasser, 400ppm present, so to a 500litre tank, I am only adding .8ppm of Ca for every litre of "saturated" PK (apparently the P stands for power, lol, can think of more colourful words to describe......).
Fortunately, I have my fans running 24/7, resulting in an evaporation rate of 8L per day.

That's a total of 6.4ppm of Ca per day...??/
 
@irie ivan thats why I first never understood why people use kalk, it adds so little calcium with the resulting pH spike produced.

Very interesting findings. I don't think I want this P kak....can't remember what you said the P stands for :p
 
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The k stands for klap i think... Something i too often wanna give people who sell rubbish.... Or myself for having to buy because I sidnt plan properly...
But let's not judge prematurely, I'll buy another batch, test it properly and compare a few brands...
Gotta get my pH pen sorted first.
There are ways to increase potency, vinegar fosing will increase by up to 30 odd %.
Figures generally toted for saturated kw is around 800ppm, which changes things dramatically....
If real world figures>>> equates to just short of 13ppm Ca added per day..... In my case.
Can save significantly on reef buider and reef adv Ca in that case....
Anybody have some kalk to donate?
 
Thanks @NO3 for the compliment, but as Carlos said, I am not the only one with valuable input….. @Midnight Reefer, corrected my answer, regarding the sir part, I think we’ll leave that for those who wears ties and or have beards……
Would love for SIR @Nemos Janitor to elaborate on the brittle skeletons and especially the skeletal breathing issues suspected…… The documentation is out there.
Not going to ramble too much about kalkwasser, there is way to much information on good old google….
ust to elaborate a bit for the newbies (as mentioned, there seems to be a lack of understanding / knowledge of this potentially wonderful / deadly white powder).
Essentially what Kalkwasser is, is a solution of Calcium Hydroxide in water(usually RO), with an extremely high pH, used by aquarists to increase pH, and add Calcium and alkalinity in a balanced (i.o.w. as used in calcification) fashion. Further benefits include precipitation of metals such as copper PO4 and other harmful substances.
The powder is not very soluble in fresh water, and only about half a teaspoon will dissolve in fresh water, yielding a pH close to 12!!! Yes, this stuff is caustic and aquarists should wear protective clothes and not breathe in the powder…..
An overdose in your tank will increase pH and will most likely wipe out most, if not all, of your livestock….. Sounds scary……
That being said, it is still a very useful way of supplementing alkalinity and calcium, raising pH and doing its bit to make PO4 les available to nuisance algae.
The most important thing to note with kalkwasser addition is simply to do it slowly, No more than ½ liter per hour of saturated kalk per 200 litres of tank volume is what I would consider the max or, when using the slurry method (google it) to do so cautiously and use a pH pen!
I use it in my top up reservoir as follows, simply judge the amount of water I added to my reservoir, and add two tsp per litre of kalk powder, stir and let it settle. I add more than needed, due to the nature of kalk to react with CO2 in the water and precipitate in the useless form of calciumcarbonate. To avoid excessive amounts being added by my atu, I have the following fail safes in place:
I turn off the atu for a few hours after mixing in kalk powder. This gives the solution time to settle nd avoids addition of undissolved powder to the aquarium.
My atu is on a timer, 15min on and 30 min off.
A tap on the airline coming from my atu ensures a slow drip rate.
As great a supplement as this powder is, it is important to also remember the following:
It does not add a lot of calcium and alkalinity, so in a tank with heavy calcification rates (read sps dominated) it is unlikely to keep up with demand. There are ways to increase its effectiveness such as increasing evaporation rates and adding vinegar to the solution( 3ml per litre)…. Again, google it.
Kalkwasser does help a great deal with biologically available Ca and Alk, which encourages calcification, yet it does not add Mg and Sr, and a system solely reliant on kalkwasser will eventually become depleted in other elements taken up by calcification. Perhaps this is what SIR @Nemos Janitor was pointing towards?
Regarding the addition of SR an Mg in Kalkwasser, another post shortly.

Thank you for the mention Ivan. I have reverted to the philosophy, pay for info. Yes it sucks, but as the sayings gos, a lot is for free ..
 
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