trythechi on ZEOvit.com
I would'nt say Balling was cheaper than an CA Rx on my size tank - the hardware is roughly the same cost, as are the comsumables.
The theoretical advantage is that you can dial in the preice values of KH , CA, Mg, as these are dosed independantly. Th edisadvantage is that its much easier to mess with the Ionic ballance unless, you keep a diligent regime.
After 2 months into Balling, my weekly readings arent much more stable than the old CA Rx provided TBH. My wife says the tank doesnt look as good as it did before the change over, and I think she's right, so I'v more fine tuning to do.
Based on my experience so far - I wouldnt rate it as an upgrade compared with a CaRx.
Cheers
Simon
PS This is the recepie I'm using - text from Ralph a German reefer and TOTM winner over on RC:
"NaHCO3 84 g/l
CaCl2*2H2O 73.5 g/l
CaCl2(whithout chrystalwater, as a replacement of the above) 55.5 g/l
MgCl2*6H2O 101.5 g/l
NaCl free salt 25 g/l
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Why I use such strange concentrations?
Thinking about chemical reactions of this kind, the number of molecules/ions is, whats interesting, not the gram of powder. To be able to calculate with those, you need the molecular weight of the chemicals.
It is given in gram/mol (a Mol is 6.023 * 10^23 particles (molecules).
NaHCO3
Having to start somewhere, NaHCO3 seems to be where to do it. NaHCO3 has a somewhat poor solutability in water, which is only 95.5 g/l at 20 degree centigrade).
To be able to solute it relatively easy, one has to reduce the amount of it a little to not hit the extremes.
Well, when thinking about moleculeweights etc., the idea of using 84 g/l, which is exactly 1 mol of NaHCO3 in one liter is quite obvious.
So concentration of NaHCO3 is 84 g/liter which is also 1 mol/liter.
CaCl2*2H2O or CaCl2 waterfree
To get a concentration here is relatively easy.
Wouldn't it be great to use the same volume of all the different solutions, when dosing?
Well, here you are: If reacting, one molecule of Ca uses two of HCO3.
Following this the concentration will have to be 0.5 mol/l, because that of NaHCO3 is 1 mol/l.
Half a mol of CaCl2*2H2O would be 73.5 g.
If useing CaCl2(waterfree), half a mol of that would be 55.5 g.
MgCl2*6H2O
hoping, that Mg also reacts with HCO3 like Ca does, the concentration may also be 0.5 mol/l.
Half a mol of MgCl2*6H2O would be 101.5 g.
NaCl free salt
to be able do dose simply the same amount, than that of the others, I'll calculate the concentration analog to that of the NaHCO3 solution.
The fact you have to know to do so is, that 70% of the salts in our oceans is NaCl.
NaCl's molweight is 58.44 g/mol.
If 70% is the NaCl, so the rest (30 %) is the NaCl-free salt.
58.44/70*30=25 gram (in one liter).
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The above solutions mean, that based on say your Ca addition, you can easily determine how much to dose.
dosing 10ml of the CaCl2*2H2O solution, means you'll have to dose also 10ml of the NaHCO3 and also 10ml of the NaCl-free salt.
Theoretically, MgCl2*6H2O is to be treated like CaCl2*2H2O, but reality shows, that Mg is not totally used as HCO3, so the NaHCO3 is a little different (volume).
Of course the solutions can be set up differently or dosed independently to hold/correct the different figures.
A good start to dose automatically is to know how much Ca and Mg - solution is to be dosed, add the volumes and use the resulting volume as NaHCO3 volume.
The NaCl free salt solution volume is the same as NaHCO3.
If doing larger corrections (initially) pls. dose in several days and dose Mg first, because Mg ions help to keep Ca ions in solution (not falling out).
Dosage of CaCl2 without NaHCO3 will raise Ca and reduce your KH (hardness) and dosage of NaHCO3 without CaCl2 will raise your KH."
source: http://www.zeovit.com/forums/showthread.php?t=9529