dolomite for calcium reactors to boost magnesium

[apollothesun]

has anybody tried putting dolimite mixed in with coral skeleton into their calcium reactors to boost or maintain magnesium levels in there aqaurium?
was wondering where i can purchase some and how much to put in a calcium reactor. also any benefits or loses in using dolomite.

 

[loohunter]

Dolomite doesnt really do much and IMO isnt worth the hastle. Dosing a good balanced additive with Mg chloride and Mg sulfate is the easiest way to go. If you make sure that your water change water has sufficient mg to begin with it helps alot.

Don
i found this on another dolomite disscusion

 

[loohunter]

http://www.reeffrontiers.com/forums/showthread.php?t=23015&highlight=dolomite
see if this works this should be the link

 

[amashun]

I do, the one that i got work out pretty good. I never dose MG in the tank and it keeps up at around 1300ppm.

My tank is a mixed reef sps dominated and i put around 10% Dolomite in my reactor.

HTH

edit:
"Dolomite in Calcium Reactor

If a calcium reactor is already used on the reef system, then it can simply be a matter of adding a small amount of dolomite to the substrate used within the reactor. Dolomite is a mineral containing both calcium and magnesium carbonate, CaMg(CO3)2. As it is dissolved in the lower pH environment in the reactor, both the magnesium and calcium are released into the water. The amount used in the reactor will have to be adjuested so that the correct balance can be found between usage in the aquarium system and that supplied by the reactor. A good percentage to start with is around 20% of the substrate contained within the reactor, then just increase or decrease the percentage as required by monitoring the magnesium concentration."
http://ozreef.org/journal/1998_may:_moving_a_reef.html

 

[apollothesun]

I do, the one that i got work out pretty good. I never dose MG in the tank and it keeps up at around 1300ppm.

My tank is a mixed reef sps dominated and i put around 10% Dolomite in my reactor.

HTH

edit:
"Dolomite in Calcium Reactor

If a calcium reactor is already used on the reef system, then it can simply be a matter of adding a small amount of dolomite to the substrate used within the reactor. Dolomite is a mineral containing both calcium and magnesium carbonate, CaMg(CO3)2. As it is dissolved in the lower pH environment in the reactor, both the magnesium and calcium are released into the water. The amount used in the reactor will have to be adjuested so that the correct balance can be found between usage in the aquarium system and that supplied by the reactor. A good percentage to start with is around 20% of the substrate contained within the reactor, then just increase or decrease the percentage as required by monitoring the magnesium concentration."
http://ozreef.org/journal/1998_may:_moving_a_reef.html

where do you purchase your dolomite? do you mix the media or section it off?

 

[amashun]

Hi, i got it from my local reef club group buy. I section it off but my friend mixed them up with the CA media. we both have no dramas.

 

[morgan]

aquamedic makes some
loohunter how could adding dolomite to a reactor not be easyer then having to rember to dose additives

 

[loohunter]

aquamedic makes some
loohunter how could adding dolomite to a reactor not be easyer then having to rember to dose additives

i have no experience with dolomite and i remember it came up in disscusion before so i did a quick search and this is what i found. i dont even have to supp. magnesium, but when i do i will go to my gym and buy lifting chalk. it is magnesium cloride, and i will slowly drip it. that way i can easily keep track of how much mag is going in my system.
i am only speculating that maybe potential probs with dolomite could be it melts down at a different rate than the rx media. also i would assume that it comes from the ground, meaning there could be other things in it other than mag. all the things i have listed in the second paragraph i dont know to be true. i'm just thinking outside the box, but i do know that if my tank needs a supp. i am going to use something that is tried and true and dosent leave much question.

 

[Boomer]

The purpose behind Dolomite is not to raise the Mg++ but to keep it at the level you want it at once it is there. Allot of this depends on what type of Dolomite you are using. In this hobby there is a very large misunderstanding of what it really is. It comes from the term "Dolomite" which is either a rock or mineral. The mineral is Dolomite Ca, Mg(CO3)2. About nobody is using this. "dolomite" the rock, at times called Dolostone, is where there is a percentage of Calcite -Dolomite. dolomite/dolostone is only when it is 90 % or greater Dolomite the mineral. Most that go get there own are really getting dolomitic limestone or limitic/calcitic dolomite, which are much lower in Dolomite.

> 90 % Calcite & 0 - 10 % Dolomite = Limestone

90 -50 % Calcite & 10 -50 % Dolomite = Dolomitic Limestone

10 - 50 % Calcite & 90 - 50 % Dolomite = Calcitic Dolomite

0 - 10 % Calcite and > 90 - 100 % Dolomite = Dolomite (Dolostone)



LS---------DL--------------CL-------------D

-----Increasing in the mineral Dolomite ---->>


0---------10--------------50-------------90-100 % Dolomite

<<<-----Increasing in the mineral Calcite ----

90-100% Calcite----------50-----------10--------0


Pure Dolomite is harder to dissolve than Calcite. Meaning, it usually requires a slightly lower reactor pH, be it the mineral or rock. The Calcite will also dissolve easier than the Dolomite in the rock. This is often the reason behind the % of dolomite suggested. Normally it is to start with 10 %. The reason behind this is Dolomite has twice the Alk of Calcite or Aragonite. So, if you use to much the Alk can get really high.

The best Dolomite media there is "Activated Dolomite", where it gives off Mg++ more readly than normal Dolomite. It goes through a process called Mechano-chemical activation, which is used for increasing the reaction activity of solids, which makes the Dolomite more soluble at or near the same pH of Aragonite or Calcite. The only one I know of that uses this type is the Zeomag from the Zeovit people.

 

[amashun]

Great info Boomer. thank you for the detail explanation.

I have one more question, for the Dolomite, would you think there will be slightly different when they are in different sizes? i mean if you have large and small size of Calcitic Dolomite. would the smaller one dissolve quicker?

Many thanks,
Adrian

 

[Boomer]

The smaller it is the faster it will dissolve. That is about the same as anything, i.e., 1^3ft of a bunch of 1^2 ice pieces will dissolve faster than 1^3 ft of a single piece of block ice. But, lets not get carried away with to small or it will turn into a brick in your reactor, just like some sand beds do or a big wad of hard mud. ~ 1/4- 1/2 " is a nice size for reactor media.

 

[Poseidon]

How about using SeaChem's Gray Coast Calcite in a reactor? I have a Ca reactor that holds 50 pounds of media, and I have maybe 2 or 3 pounds of Gray coast in the reactor as well. I keep the pH of the reactor from 6.6-6.8, and my Mg is constantly low, around 1000ppm versus a Ca level of 400, and an Alk of 9-10.

My tank is STUFFED with SPS, including several large caps. I get good growth, but I am perplexed as to why I can't seem to get the Mg level to 1200.

Thanks!

 

[apollothesun]

anybody know where to get activated dolomite? (thanks boomer for the heads up)

 

[Boomer]

Zeomag
http://www.zeovitusa.com/product.php?productid=16177&cat=251&page=1

Gray Coast Calcite

It *may be fine but will require a tad lower pH than Aragonite. However, I do not know how it will assay out with unwanted impurities. So, you are on your own. This product also has allot of dust, which may initially raise the Alk, pH and Ca++. Me I would stay away.

 

[amashun]

The smaller it is the faster it will dissolve. That is about the same as anything, i.e., 1^3ft of a bunch of 1^2 ice pieces will dissolve faster than 1^3 ft of a single piece of block ice. But, lets not get carried away with to small or it will turn into a brick in your reactor, just like some sand beds do or a big wad of hard mud. ~ 1/4- 1/2 " is a nice size for reactor media.

thanks Boomer. yeah, the media that i got is really small size. probably smaller than 1/4

Cheers for that info.

 

[apollothesun]

thinking about getting this, what do you think boomer?
http://www.premiumaquatics.com/Merc...&Product_Code=ESTE-DOL25&Category_Code=cmedia

 

[Boomer]

I'm sure it will work but it would nice to see a data sheet on it to see what "grade" it is.

 

[apollothesun]

wanted to give an update, ive tried this and i noticed my alkalinity wanders everyday. ive, also noticed the magnesium fluctuates to much too. ive sinced been dosing magnesium chloride with magnesium sulfate and now my alkalinity and magnesium are stable.
the left over dolomite i put into a tlf reactor and put it at the end of my denitrator. i dont know if that will desolve but i see no ill effects.

 

[MAC2]

Are you still dosing this way, or did you find something else to put in your calcium reactor?