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

hi sorry to sound stupid but can somebody explain the carx reactor and how it works would appreciate it thanks

its a tube filled with calcium carbonate, we then mix CO2 into the saltwater to form carboxylic acid which dissolves the calcium into its constituents, Ca, Alk, Mg and Sr thus dosing our tank, it does lower ph as we run the ph in the reactor at 6.5-6.8
 
where do you source your kalk?
I use Warren Chem, and they deliver to your door. In the region of R750 a bag. I also the big bags of sodium carbonate anhydrous, calcium chloride dihydrate. Hope I spelt them right.
 
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hi sorry to sound stupid but can somebody explain the carx reactor and how it works would appreciate it thanks

A calcium reactor works by adding crushed coral media, actually the skeletons of marine corals into a reactor. You then need to decrease the pH inside the reactor to dissolve the media, this happens at around a pH of 7. The lower the pH the more Ca is dissolved. This happens in a natural Ca, alk, mg ratio as coral skeletons are made up of the perfect ratio. The more hard corals you have in your tank the lower the pH needs to be in your reactor. I kept my pH controller at 6.55
Also, with a carx you will need CO2. This is what lowers the pH in the reactor.
pH in the reactor is controlled by the bubble rate of the CO2 and the drip rate coming from the reactor.
You don't need too much CO2 to keep the pH low within the reactor and when you get the balance right between the drip rate and bubble rate all you need to do is adjust the pH number on your pH controller.
I, personally, have found that a carx is one of the most invaluable pieces of equipment in my arsenal in keeping sps, it's cheap to run, never worry about changing dosing bottles or working out ratios, blah, blah, blah.
It costs me about R500 a year, and I had a 95% sps reef.
The initial outlay is expensive, but goodbye to bottles and dosers. ....
 
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thanks guys for the explanation I was wondering why it was called a carx reactor when majority of the web sites we browse just call it a calcuim reactor is there any difference between the to
 
thanks guys for the explanation I was wondering why it was called a carx reactor when majority of the web sites we browse just call it a calcuim reactor is there any difference between the to

CaRx = Calcium Reactor , where Rx is a abbr for reactor

its normally refered to as a Carx or calcium reactor
 
@shan for such a simple product, its really beneficial.
the simplicity, easy of use, cost , any tank under 150L can be maintained using kalk with out other suppliments
 
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No MAN , be nice to hear from him what makes it so important, how it helps marine tanks and is it as complicated as everyone makes it out to be, more for the guys that dont use it and would like to learn how!
Nice to have some solid input from a guy that has been in the game for ages !
 
Instead of mixing a solution of max saturation make a solution that is slightly less saturated, half maybe or even measure it at slightly higher than the ph you want then dose it to the tank!

@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.
 
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Will write a bit tonight, promise. Simply slowing the rate of addition (a tap on the top up pump outlet)does wonders to prevent pH spike.
 
@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.

Something wrong there, maybe? My pH stays very stable. I have a probe to measure and a graph to over time to inspect it.
 
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No MAN , be nice to hear from him what makes it so important, how it helps marine tanks and is it as complicated as everyone makes it out to be, more for the guys that dont use it and would like to learn how!
Nice to have some solid input from a guy that has been in the game for ages !

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.
 
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@carlosdeandrade Maybe you don't see a spike cus ur system has awesome buffering capacity, or as @irie ivan mentioned, maybe you dose it slowly? But damn, wish I had a fancy probe that makes a graph :( fancy witchcraft that :p

Only been using kalk for several months, so I'm learning still!!

I do hate pH swings though, especially when I have a 'boss' to keep an eye on me with an expensive pH probe! ;)

Am I wrong when I say; With a Ca reactor running on full blast and properly dialed in, that effluent is gonna keep the pH depressed although it's producing a shed load of carbonate and goodies, in comes the hydroxide to auto dose aswell, via topup water to balance the pH?

And Is it all agreed that any kalkwasser left exposed to air will react with CO2, causing a useless precipitate of inert calcium carbonate over time?

And anyone tried one of those 'new' kalk+2 mixes with Mg and Sr in aswell? Brightwell does one I believe.

And do those extra secondary chambers help on fancy calcium reactors?
 
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Am I wrong when I say; With a Ca reactor running on full blast and properly dialed in, that effluent is gonna keep the pH depressed although it's producing a shed load of carbonate and goodies, in comes the hydroxide to auto dose aswell, via topup water to balance the pH ?
YES, it will balance the tendency of a CARX to push down pH. So.... NO, you are not wrong in saying that. 100% correct.

And Is it all agreed that any kalkwasser left exposed to air will react with CO2, causing a useless precipitate of inert calcium carbonate over time?

YES

And anyone tried one of those 'new' kalk+2 mixes with Mg and Sr in aswell? Brightwell does one I believe.
At full strength, Kalkwasser will precipitate most metals, what is the biological availability of the Mg and Sr in the "souped up" kalk?
 
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@irie ivan, thanks for the replies Sir Ivan. But can you correct my statement on the first part your reply? will a system run at 8.1-8.3 with a reactor going full steam for SPS growth and no kalk?

That is a very sensible statement about the metal's behaviour. You are 100% correct and it's that's an important behaviour of kalk I will now remember!

But.....I got curious.....is Brightwell selling somthing ridiculous?....or snake powder?

It turns out Brightwell say what chemicals they put in most products on the website, not specifics such as hydrous/anhydrous but go look. 'technical button' and look at ingredients.

So I got extremely curious and needed to know what they suggest 'kalk+2' is made from, so it's; Calcium hydroxide, Strontium hydroxide, Magnesium hydroxide.

Calcium (min) 54.20% (542,000 ppm), Strontium (min) 1.00% (10,000 ppm), Magnesium (min) 0.15% (1,500 ppm).

Notice how the Mg is 0.15% as opposed to the Sr of 1.00%. possibly to do with hydrous/anhydrous etc?

But more importantly, does it sound like it could work? @irie ivan and @carlosdeandrade ?Strontium isn't something to mess around with and never used hydroxides of Mg or Sr.

I don't like Brightwell , they sell Lugol's for around R475 for 125ml. I buy medical grade lugols at pharmacist at R200 for 500ml and the same goes for several of their other 'products'.

They are an awesome resource to 'poach' D.I.Y chemical additive ideas though, holy moly!! already scheming about the amino acids......
 
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