[Aqua-Digital]

Here is an amazing article on Hans Werner Ballings method, well written and explains a lot for those that wish to follow the original balling method.

Many thanks to our friends at Ultimate Reef in the UK for this well written article
Written for UltimateReef by Alan Mullett (AlanM).
Published November, 2007 at UltimateReef.com

The Balling Method

INTRODUCTION
The primary elements consumed by corals and coralline algae need to be replaced at a rate which keeps up with the demand, with the aim that the levels of these elements remains stable. Stability is a key word often used and quite rightly so as in a reef environment the short term levels of elements (short as in decades) remain very constant with the consequence that reef inhabitants have not evolved for rapid changes in water parameters.

THE PRIMARY ELEMENTS
There will probably be debate between reef keepers for as longs as there are reef keepers about the aspects of the reef environment which are important to the survival and growth of coral inhabitants. For this I am going to limit the list to four which are:
Calcium
Carbonates
Magnesium
Everything else
The “Everything else” category is somewhat a catch all, but a valid one as you will see in the detail.

THE INGREDIENTS
It would be very nice if we could just take a drop of pure calcium, a drop of carbonate, a drop of magnesium and a drop of everything else and just drop them into the tank. The levels would all be added to and problem solved.

But we can’t just do that, the forms that they would take would not make them readily biologically available which is the whole point of doing it, so we need to look at other avenues.

What Hans Balling documented is a way of adding versions which can become biologically available and in combination which can be balanced with the other elements within the environment.

The short list of items to be added becomes:
Calcium chloride dihydrate (CaCl2-2H20)
Sodium Hydrogen Carbonate (Na HCO3) (aka Sodium bicarbonate – Baking Soda)
Magnesium Chloride Hexahydrate (MgCl2-6H2O)
NaCl free reef salts – your tub of reef crystals without the table salt.
Chuck them in, give it all a stir and there you go.

HOW TO BAKE A CAKE
Ok, so just chucking them all in and sticking it in the oven probably won’t get you a very nice cake, trust me, been there, lumps of dry flour and baking powder don’t do wonders for the taste.

In the same way throwing lots of powders into your tank isn’t going to endear you to your livestock either. They will probably do the obvious thing and fall over and die. So what we need to do is add them in a way that benefits them rather than kills them.

And at some point explain why we need #4 above.

If you look at #1 and #2 on the list you will find we are adding things we want:
Calcium
Carbonates

and things we didn’t want:
chloride
sodium

Now the ones of you who are still awake will notice that chloride and sodium look familiar in combination, Sodium Chloride may be one of the few compounds that most people know, common table salt, and is about 70% of the bucket of reef salts.

So if we do add #1 and #2 we end up with the additional calcium and carbonates which is good, and also more Sodium Chloride which we didn’t want, and so we need to do something about it. We can’t just pull it out of the water, it’s not that easy, but what we can do is add everything else from the bucket of reef salt to balance it all up again. So we add #4, the NaCl Free Reef Salts. With that addition we have now added:
Calcium
Carbonates
Reef Salt
Water

which looks quite a bit better. The only downside now is that we have added lots of salty liquid to the tank, a bit like topping up with mixed water rather than RO water, a mistake often made by beginners.

If you imagine your tank level or sump return level if you have one then the levels will now be higher than when we started. If we ignore evaporation for a moment then eventually your tank will overflow and you’ll have a wet floor. Thanks Hans! If we put evaporation back into play what will happen is that you will top up with less RO than normal which will increase the salinity of your tank over time.

The solution is simple; just remove as much as you add. Sum up the volumes in #1, #2 and #4 and then just take out that much tank water. It’ll put the levels back on track letting your top up do its job.

And, simply put, that is the basics of Balling. Add stuff, balance it out, and level it out.

A CHEMISTRY PRIMER, OR HOW TO WEIGH AN ATOM
So where were we, ah yes, we’ve just taken the cake out of the oven and it looks “interesting”. A slab of brown cake like stuff, looking good. We cut into it and the whole thing falls apart, and another aspect to cookery becomes apparent: you need to measure your ingredients. Just pouring stuff into the bowl doesn’t work.

So, how much do we use? For that we have to delve a little into chemistry looking at how much “stuff” weighs so we can weight it out.

The important factor is that we add calcium and carbonate in the same relative quantity that they are consumed. Biologically the consumption is

Ca2++2HCO3 <=> CaCO3 + CO2 + H2O

which means take one atom of Calcium and two molecules of Carbonate which combine to form one molecule of CalciumCarbonate, one molecule of carbon dioxide and one molecule of water.

From this we can tell several things:
That it is the Calcium (Ca) and Bicarbonate (HCO3) that are the inputs
That two units of Bicarbonate are used for each unit of Calcium
That carbon dioxide and water are by-products of calcification
So we need to ensure that we add the ingredients in the same proportion, that is two units of Bicarbonate for each unit of Calcium, and that we balance out the resulting NaCl with NaCl-Free salts.

In chemistry most measurements of the ‘amount’ of a molecule Is done in mol. Each mol of a substance contains the same number of elementary entities (atoms, molecules, etc), and normally it is the gram-mole which is used. A gram-mole is the quantity of a substance whose mass in grams is equal to its formula weight. This makes it quite easy to weight out substances so that they are in the relative quantities we need.

The important bit is working out the formula weight and for that we need to understand a little more about atoms. Each atom has a particular mass and these are well known quantities and appear on a periodic table of elements. The important elements to us for this purpose are:

Element Atomic number Atomic weight
Hydrogen (H) 1 1.00794
Carbon 6 12.0107
Oxygen (O) 8 15.9994
Sodium (Na) 11 22.9898
Magnesium (Mg) 12 24.305
Chloride (Cl) 17 35.453
Calcium (Ca) 20 40.078


and the way to determine the molar mass is to add up all of the bits to get the total atomic weight for one entity and then that amount in grams is one mole. Showing this makes it much easier:

Determine the atomic weight of CaCl2 - 2H20 by adding the atomic weights of the parts:

First determine the atomic weight of CaCl2

40.078 + 2x35.453 = 110.984

Then determine the atomic weight of H2O

2x1.00794 + 15.9994 = 18.01528

Then add them together remembering we have two molecules of water

110.984 + 2x18.01528 = 147.01

Determine the atomic weight of NaHCO3:

2.9898 + 1.00794 + 12.0107 + 3x15.9994 = 84.00664

So from this we now know that one mole of CaCl2-2H20 weighs 147.01 grams and one mole of NaHCO3 weighs 84.00664 grams. Thus as we need twice as much of one to the other it is simply a case of weighing out the proportionate amount, which is where Balling gets his often used figures of:
147g of CaCl2-2H2O
168g of NaHCO3

and he dilutes each of those to 2L of water, which now means that the same quantity of water from each contains proportionally correct amounts of the two ingredients. That dilution is done to a total volume of 2L, not 2L of water plus the ingredients, so the best way is to measure out 1.5L of water, add the chemicals and then top up to 2L by adding more water.

In those two mixes we now are adding those bits we want, and those bits we don’t which as we noted before is the Na from the NaHCO3 and the Cl2 from the CaCl2. Fortunately we are adding twice as much NaHCO3 as we are CaCl2 so for each unit of addition we have two units of NaCl resulting. So for each 2L added we are adding two moles of NaCl.

The atomic mass of NaCl is 58.443 which means we are adding 116.89 grams of NaCl for each 2L mix we add. As NaCl represents 70% of the ingredients of marine salts we now have to add the remaining 30% to get to a full marine salt mix. As 70% weighs 116.89 grams it means 100% weighs 167g, meaning that the 30% weighs 50 grams, once again the figure that Balling uses as the third container, a mix of 50g of NaCl-free salts to 2L water.

So we have ended up with three mixes of which we add in the same quantities to ensure a balanced addition that adds Calcium, Carbonate and balanced marine water.