How do I NOT overdo it adding kalkwasser through my ATO?

[cherubfish pair]

I have very few corals so there is very little demand but I have to start somewhere.

Does the Calcium keep accumulating as water is replaced due to evaporation or can water changes take care of that?

[behlke]

I am not exactly sure what you asked in you question, but I will take a stab at it.

The corals use Ca and ALK to make their skeletons. If nothing was done to the tank, the corals would eventually deplete the Ca and ALK from the water. Kalk replenishes both Ca and ALK in the appropriate ratio to the tank water. There are several ways to add Kalk to the aquarium. Probably the most common way is to add kalk to the ATO. Another option is to mix a gallon of kalkwasser and slowly drip it into the aquarium. The third, which I do, is to mix kalkwasser and slowly pour it into the aquarium in a high flow area. The second and third options give you more control over when, and how much, Kalk is added to the aquarium. In the ATO you can mix in Kalk at whichever concentration you think you need and then adjust it as needed.

I hope this answers your question.

[Psyops]

Honestly at this point if water changes are keeping your calcium and alk levels ok, then you don't need to start kalk yet. You only start dosing when your corals are depleting the levels beyond water changes. Hope this helps.

Alex

[Mattewell]

Make sure you have alk and Ca test kits. If they are rising over the course of the week, then add less kalk powder to the top off water. You want to get to a point were they stay stable.

Would anyone know what amount would be a good starting point for low demand?

[jerpa]

I wouldt start with 1 teaspoon of kalk per gallon of RO water and adjust it up or down from there.

It is best dosed at a very slow rate. Peristaltic pumps work well for this application. Hand dosing can work for very low consumption tanks but must be done carefully to avoid large swings in PH.

[disc1]

If you do find that you need some supplementation and saturated kalk is too much then just cut back. There's no rule that says you have to saturate the kalk, you can simply add less. There's also no rule that says all the top off water has to come from the same bucket. You can run a certain amount of kalk per day and switch over to regular ro water for the rest of the top off.

[Lynxone]

Originally Posted by disc1

if you do find that you need some supplementation and saturated kalk is too much then just cut back. There's no rule that says you have to saturate the kalk, you can simply add less. There's also no rule that says all the top off water has to come from the same bucket. You can run a certain amount of kalk per day and switch over to regular ro water for the rest of the top off.

+1

[cherubfish pair]

Originally Posted by Mattewell

Make sure you have alk and Ca test kits. If they are rising over the course of the week, then add less kalk powder to the top off water. You want to get to a point were they stay stable.

Would anyone know what amount would be a good starting point for low demand?

I would like to work up to a kalk stirrer. This would dispense saturated kalkwasser? How do you keep from overdoing it this way besides testing and water changes (and pH monitoring/controlling I presume)?

[bertoni]

Kalk reactors don't seem to produce saturated limewater. I don't know why. Most tanks need more calcium and alkalinity than Kalkwasser can supply, because it's such a dilute supplement, so they don't get overdosed, but every tank is different.

[Yogre]

Originally Posted by cherubfish pair

I would like to work up to a kalk stirrer. This would dispense saturated kalkwasser? How do you keep from overdoing it this way besides testing and water changes (and pH monitoring/controlling I presume)?

There really isn't anyway I can think of other than frequent testing of Ca and alkalinity to know if a kalk stirrer is too much, too little, or just right for your tank.

When I started using a stirrer 3 years ago, having the stirrer plumbed into my ATO easily kept up with my tank's demand. Now that my SPS pieces and clam are much bigger, I'm starting to see that Ca runs a little low from time to time.

Once I see that Ca is consistently too low, I'll have to consider adding either two part dosing or a Ca reactor to my kalk dosing regime. I will probably always use kalk, as it helps keep pH up and my tank's pH has always tended to run low.

[aaroz]

Kalkwasser IS a wonder substance for saltwater aquaria!

Its only draw back is it should be added outside of the photoperiod when CO2 levels are likely to be elevated (thus pH low, it can be overdosed WRT pH but WILL NOT overdose Calcium and Alkalinity.

Balanced aquaria ph 8.2, Ca 400mg/l kH 7, Mg 1300 all ish values. Excess Kalkwasser will precipitate as CaCO3 (limestone) and attract phosphates, organics amongst others It is brilliant stuff BRILLIANT i tell you all!

Bertoni...A saturated kalk mix has a pH of 12.4, if a kalk mixer has a pH of less clean it out because what is stirring is not only calcium hydroxide but Calcium Carbonate (Hydroxide that has reacted with atmospheric CO2 or CO2 dissolved in supply water) and thus the mixture is not full strength saturated hydroxide solution.

When it comes to kalkwasser JUST DO IT it is the best supplement by a mile for saltwater aquaria! But do it slow, every day and at the right time with a fresh mix, oh and have half an eye on the pH.

Aaroz

[bertoni]

Dosing limewater during the day is fine, IME. It is a very dilute additive, and aeration will bring the pH down fairly quickly in most systems. I don't know of any evidence that Kalk will remove phosphate or organics, but it is inexpensive, doesn't upset the ionic balance of the system, and the pH boost is useful in a lot of systems.

I don't know why Kalk reactors don't seem to produce saturated lime. Maybe the effect is more prominent if the reactor isn't sealed against air contact. Maybe the reports have been wrong. I've never run a reactor, so I can't be sure.

[AcroporAddict]

In my 465 gallon SPS tank I ran an MRC Standard Nilsen sealed kalk stirrer (timed mixing) with a Tunze ATO pushing all evaporative makeup through it, and the pH of the tank would max out at about 8.0. I recently switched to a non-sealed (got a lid but not airtight like the MRC) Avast Marine K2 stirrer (24/7 slow stir), and now the tank goes to 8.2, so for whatever reason the constant slow stir, open to air type Avast stirrer is letting more saturated kalk water through. The Avast stirrer is much easier to service as well.

[tmz]

Constant stirring in an unsealed container introduces CO2 which weakens the limewater( kalk) via precipitation. Of course, if there is extra kalk on the bottom it should offset that but will use more supplement overall a some of it will just tun into useless calcium carbonate precipitant. Constant stirring also keeps precipitated impruities from fully settling on the bottom.
Constant stirring in a sealed container keeps impurities and undissolved kalk suspended in the water which makes it very difficult to deliver clear saturated lime water.
A still reservoir with a lid ,like a brute can or salt bucket works well if stirred when filled ; left to settle for an hour or two and then dosed with a peristaltic or diaphram pump. 24/7 dosing spread out evenly in small amounts at one time is fine ,ime. Still lime water in a lidded container won't loose it's strength for weeks.
I prefer to set a daily dose rather than use an ato, per se ,20 liters in my case for 650 gallons of water volume which approximates my daily top off. Seasonal shortfalls in top off are easily remedied with a direct addition of some extra ro water .

[A. Grandis]

Hey Tom, how're you doing!! Nice to see you around...

I'll leave my $.02 here too...

I have 2 tanks with kalk reactors and just love them!!
One, in my 75gal., is the AquaMedic. Sealed and with the stirrer. Works fine!! The only drawback is that the motor, running 24/7, gets a little warm, but it doesn't play a lot with the dissolution and I tend to add a little more powder than I need because of that. That's not a problem because kalk is relatively inexpensive anyway.

I've got a home made stirrer for my new 125gal. and I like that even better than the AquaMedic on my 75gal!! The new stirrer isn't sealed and works just great!!!! The cover just sits on it, like the Avast.

I have no hard corals at all because it's illegal to keep them here in hawaii, so my kalk reactors are mostly to help with a little bit of calcium and alkalinity of my coralline, besides the neutralization of some organics in the systems.

I still have to use some buffer to be able to keep my zoanthids and coralline algae flourishing at it's best, but kalk helps a lot and it's added every day, ATO.

I use peristaltic pumps for each of the reactors with ATO and there is never pH higher than 8.3. Even at the end of the light cycle. No high pH...
It is so hard for me to understand having pH at 8.4+. I've never had that happened through all my 18+ years of maintaining natural systems and Kalk.

I wish I could go much deeper understanding the REAL relationship of Alk, Mg and Ca!! To me this is the hardest subject because there are so many variables and every one says one thing. I guess the differences between systems are a great deal when comes to really put the math on the paper.

Grandis.

[blanden.adam]

IMO, there's certainly nothing wrong with kalk reactors, but because they are the more expensive option and require more "machinery" relative to a still reservoir, there has to be a reasonable justification for using them instead of just a still reservoir.

A still reservoir mixed when filled and left covered (but not necessarily sealed) and NOT stirred, will last more than 21 days at full potency (see this article by RHF for almost anything you'd want to know about limewater in reef aquaria: http://www.reefkeeping.com/issues/2005-01/rhf/). What this means is that for at least up to 3 weeks (I've never seen a report of someone quantitatively testing it over a longer time period), a kalk reactor can only perform at the same level or worse than a still reservoir at delivering saturated limewater. There are also numerous anecdotal reports of people people have issues with the consistency of the limewater concentration coming out of kalk reactors for a variety of reasons, but this is not universally true. The safety issues with both are identical, so there is no separation between the two there. The lower cost, ease of implementation, consistent performance, and fewer points of failure make the still reservoir the clear winner IMO if one can be used.

The drawback to large still reservoirs is they take up a significant amount of space. So, if there is no space for a reasonably-sized still reservoir, then a kalk reactor might be a good solution (I mean really, who wants to mix kalk more than once a week? Certainly not me, thank you 32gallon brute can ). I will point out, however, that ATO reservoirs take up space as well, and I don't recommend hooking top off straight into an RO/DI system, so this drawback is almost a non-issue in most situations.

Some notes about my implementation scheme: I dose saturated limwater 24/7 from a 50 ml/min peristaltic pump into the return chamber of my sump pulling from a 32 gallon brute can still-reservoir in the basement. I have it hooked up to my ATO system with 2 redundant float switches (1 about 1/2 gallon higher than the other) in series wired into a 12V DC relay which switches the 120V AC outlet attached to the pump. That is plugged into a pH controller that will shut off the reactor if the tank pH reaches 8.45 indicating an on-position failure of both float switches, and will not turn on again until the tank pH drops to 8.1. I also use a fan 24/7 to increase evaporation and to normalize the amount that evaporates from day to day as on very hot days the fan is required to keep my tank cool (so instead of running it just when the tank heats up and evaporating significantly more on hot days, I just made the decision to run it all the time). As with any equipment, if something can go wrong it will go wrong eventually, but redundancy will keep your system safe if something does fail. Kalk is my favorite supplement, use it wisely and it will treat you well too

[Lpoole]

if you can get by by just water changes don't worry about it till you get enough corals to actually do some damage in the levels. But I vote for the individual dosing pump like bubblemagus for 300. And an auto top off and bam perfect levels. Like the above said depending on the evap during the year can mess it up, especially with evap in the winter. My approach is easier imo. But kalk is cheaper in the long run.

[A. Grandis]

The only problem with a reservoir with still kalk solution is that the solution itself will eventually clog the line of the dosing pump and with the reactor that safety issue is automatically solved. Unless if we could connect the tap water to the reservoir in the same fashion we do with the reactor. That's why I choose the reactor, not the reservoir, besides the large space needed for such. The reactor sits close to the sump and works great. It's so easy to clean up and service. Maintenance is only twice a month. But yeah, the space for the container would be a big issue. Specially when you leave in an apartment!!

Grandis.

[blanden.adam]

Originally Posted by A. Grandis

The only problem with a reservoir with still kalk solution is that the solution itself will eventually clog the line of the dosing pump and with the reactor that safety issue is automatically solved. Unless if we could connect the tap water to the reservoir in the same fashion we do with the reactor. That's why I choose the reactor, not the reservoir, besides the large space needed for such. The reactor sits close to the sump and works great. It's so easy to clean up and service. Maintenance is only twice a month. But yeah, the space for the container would be a big issue. Specially when you leave in an apartment!!

Grandis.

Just run a dilute acid (i.e. vinegar, or diluted muriatic acid if you so desire) solution through the line and vaccum out the sludge about once a year bam, problem solved

[Yogre]

I use a kalk reactor for a simple reason, safety. I travel for a living, and from time to time my wife has to deal with the top off tank. It's very easy for her to dump RO/DI in the top off, since it has no kalk to splash on her.

I have no doubt if she had to deal with limewater she would not be comfortable with maintaining the ATO when I'm gone.

[tmz]

I've run it from a still reservoir for about 7 years with a timed peristaltic pump; never had clogged pump or line. Never had to dose vinegar through it although that's the procedure I would use if a line clogged with precipitated calcium carbonate. I think such clogs from precipitation would be more likely in solutions carrying undissolved caclium hydroxoide powder as is more likely the case with continuous stirring of small water volumes and large amounts of calcium chloride.

The draw line for the perstaltic pump is placed several inches above the bottom and the slurry in the still reservoir set up ,so what goes through the pump and the line is fully saturated clear limewater.
I agree space is an issue and reactors can be useful but you can mix a 3 week supply or more at one time in a still reservoir stirred only once , adding a little extra to settle at the bottom should buy even more time if you choose to go larger.
I also think handling kalk powder can be a safety concern when inhaled and wouldn't want my wife messing with it.I wear a mask when handling the powder and I'm careful when stirring which is not very vigorous not to splash it into my eyes either. Those safety concerns apply to whatever device you are filling.

[tmz]

I wish I could go much deeper understanding the REAL relationship of Alk, Mg and Ca!! To me this is the hardest subject because there are so many variables and every one says one thing. I guess the differences between systems are a great deal when comes to really put the math on the paper.

Grandis.

Hi,

It's not as arcane as we tend to make it. This is my oversimplified version I hope it provides an understandable skeletal view of what's happening.

PH can be viewed most simply a measure of H+ in the water.
Pure water has a pH of about 7.0 ;lower ph means more acidity/ more H+ and vice versa.

Alkalinity is a measure of the capacity of the basic elements in the water to neutralize the H+/acidity.
Alkalinity is not a thing; it is a measure of many things .

Most of the alkalinity in seawater (96.5%) is bicarbonate/carbonate which is consumed by calcifying organisms( corals, mollusks, coraline algae, etc) . A biotic precipitation will also consume it via precipitation as calcium carbonate, when levels are high and pH is high. So, it needs to be replenished to meet consumption rates .

Magnesium slows down the growth of calcium carbonate crystals( precipitation) essentially stopping their growth,thus allowing more calcium and carbonate to remain in solution than without it.
So , if everything was constant it would be relatively simple. More alk which is basic equals higher pH and vice versa.

But it's not constant. There is a constant flow of mystery guests at the aquairum inn , all named CO2.

The aquarium lives in the air which effects the pH; the life inside it also affects ph and alkalinity.

CO2 equlibrates with the air around the tank; similarly the oceans and other bodies of water eqilibrate with the athmosphere and its 400ppm CO2. CO2 is also produced and consumed by various organisms in the tank at various times The speed of the equilibration (gas exchange ) depends largely on the surface area which is increased by agitation. it also depndens on the level ofCO2 in the surrounding air.

The CO2 level drives the pH in a real life aquarium ;not the alkalinity.

CO2 adds H+ by taking it from H2O as it hydrolizes in the water .When CO2 is reduced by gas exchange or biological acitivity like photsynthesis, the H+ is also reduced. Conversely, when CO2 in the water increases the H+ increases.

Calcium hydroxide(kalk) is unlike two part dosing or calcium reactor dosing both of which add carbonate for alkalinity.

Calcium hydrioxide(kalk) has no carbonate ; the hydroxide joins CO2 and makes carbonate CO3. It reduces CO2 in making carbonate alkalinity ; as a consequence of the CO2 use , the H+ is reduced raising the pH.

Since calcium hydroxide is dosed continuously, it keeps using CO2 in the water,ideally keeping pace with the flow of CO2 from the air and organisms. However, if too much is dosed at once it will use up too much CO2 and spike the pH and the rate of gas exchange won't provide enough new CO2 to keep up.
Ultimately, the higher levels of carbonate alkalinity calcium and pH in combination will lead to to precipitation of calcium carbonate.

[james1990]

this is one of the best kalk threads I have come across. I dose via BM dosing pump B-ionic 2 part and need to start using Kalk for PH.

So, if a still reservoir is just as efficient if not BETTER than kalk reactors, what would be the ideal container for such thing? I would think a clear glass aquarium would be best to clearly see where the sediment line is and make sure of placement of the intake (probably a rigid plastic tube is best).

does the temp matter in a kalk container? mine would go in my attic, it gets hot in there.

also, make sure any dosing pump you use can keep up with the demand your tank needs.

[A. Grandis]

Originally Posted by tmz

I've run it from a still reservoir for about 7 years with a timed peristaltic pump; never had clogged pump or line. Never had to dose vinegar through it although that's the procedure I would use if a line clogged with precipitated calcium carbonate. I think such clogs from precipitation would be more likely in solutions carrying undissolved caclium hydroxoide powder as is more likely the case with continuous stirring of small water volumes and large amounts of calcium chloride.

The draw line for the perstaltic pump is placed several inches above the bottom and the slurry in the still reservoir set up ,so what goes through the pump and the line is fully saturated clear limewater.
I agree space is an issue and reactors can be useful but you can mix a 3 week supply or more at one time in a still reservoir stirred only once , adding a little extra to settle at the bottom should buy even more time if you choose to go larger.
I also think handling kalk powder can be a safety concern when inhaled and wouldn't want my wife messing with it.I wear a mask when handling the powder and I'm careful when stirring which is not very vigorous not to splash it into my eyes either. Those safety concerns apply to whatever device you are filling.

My clogged lines (partially clogged at the ends) were from clear saturated kalk mix after min. 12hr. rest. The end of the line (manual drip system), out of the water above the sump, needed vinegar cleaning every 2 weeks or so to avoid total clogging. Back then, I used to make kalk every single day because I had no reactor and didn't have room for anything around the tank. That's why I would think that with a larger container it would be actually worse.
I used to mix a tsp per gallon.

Grandis.

[A. Grandis]

Originally Posted by tmz

I wish I could go much deeper understanding the REAL relationship of Alk, Mg and Ca!! To me this is the hardest subject because there are so many variables and every one says one thing. I guess the differences between systems are a great deal when comes to really put the math on the paper.

Grandis.

Hi,

It's not as arcane as we tend to make it. This is my oversimplified version I hope it provides an understandable skeletal view of what's happening.

PH can be viewed most simply a measure of H+ in the water.
Pure water has a pH of about 7.0 ;lower ph means more acidity/ more H+ and vice versa.

Alkalinity is a measure of the capacity of the basic elements in the water to neutralize the H+/acidity.
Alkalinity is not a thing; it is a measure of many things .

Most of the alkalinity in seawater (96.5%) is bicarbonate/carbonate which is consumed by calcifying organisms( corals, mollusks, coraline algae, etc) . A biotic precipitation will also consume it via precipitation as calcium carbonate, when levels are high and pH is high. So, it needs to be replenished to meet consumption rates .

Magnesium slows down the growth of calcium carbonate crystals( precipitation) essentially stopping their growth,thus allowing more calcium and carbonate to remain in solution than without it.
So , if everything was constant it would be relatively simple. More alk which is basic equals higher pH and vice versa.

But it's not constant. There is a constant flow of mystery guests at the aquairum inn , all named CO2.

The aquarium lives in the air which effects the pH; the life inside it also affects ph and alkalinity.

CO2 equlibrates with the air around the tank; similarly the oceans and other bodies of water eqilibrate with the athmosphere and its 400ppm CO2. CO2 is also produced and consumed by various organisms in the tank at various times The speed of the equilibration (gas exchange ) depends largely on the surface area which is increased by agitation. it also depndens on the level ofCO2 in the surrounding air.

The CO2 level drives the pH in a real life aquarium ;not the alkalinity.

CO2 adds H+ by taking it from H2O as it hydrolizes in the water .When CO2 is reduced by gas exchange or biological acitivity like photsynthesis, the H+ is also reduced. Conversely, when CO2 in the water increases the H+ increases.

Calcium hydroxide(kalk) is unlike two part dosing or calcium reactor dosing both of which add carbonate for alkalinity.

Calcium hydrioxide(kalk) has no carbonate ; the hydroxide joins CO2 and makes carbonate CO3. It reduces CO2 in making carbonate alkalinity ; as a consequence of the CO2 use , the H+ is reduced raising the pH.

Since calcium hydroxide is dosed continuously, it keeps using CO2 in the water,ideally keeping pace with the flow of CO2 from the air and organisms. However, if too much is dosed at once it will use up too much CO2 and spike the pH and the rate of gas exchange won't provide enough new CO2 to keep up.
Ultimately, the higher levels of carbonate alkalinity calcium and pH in combination will lead to to precipitation of calcium carbonate.

That's a very good way to put it!!! Thanks for the effort!!
What about Mg?

Grandis.