[Aqua-Digital]

Part 2..

SO HOW MUCH DO WE ADD THEN?
Quite simply It depends upon your consumption, and for this you may have to guess a little, or if you are currently using other additives you should be able to work it out from the statements on the bottles which often say how much the bottle adds, you can then work out how much you are adding on a daily basis.

If you are not sure then an easy way of working it out is to stop adding anything, settle for a day and then take a Calcium reading on a daily basis at the same time. The difference between them will tell you how much in ppm (aka milligrams per litre) your tank is consuming. This figure is very useful as you end up with how many grams of Calcium you need to add a day – and it’s very easy to work out from that figure how much of the mix you need to add daily.

Let's assume you have done the above daily tests and you are losing 5ppm per day of Calcium, and that you are running a 200l tank (figures chosen to be easy).

This means that you are losing:
5 mg per litre x 200 litres = 1000 milligrams, or more commonly known as 1 gram.

We know that our first mix with CaCl2-2H2O has one mole of Ca per 2L, and that one mole of Ca weighs 40.078grams, so we now know that we have to add 1/40.078 moles of Ca a day. That means we have to add 1/40.078 of the 2L mix, which works out at 50ml per day.

There you go, for a 5ppm loss in a 200l tank you have to add 50ml of each mix, and then to balance out the water levels you have to remove 150ml of water from the tank.

You could look at this as simply 5ml of each mix per ppm loss per 100l of total volume. A handy figure meaning that you don't have to understand any of the above to be able to use the Balling Method. Just multiply up for your loss and for your size tank and use that amount.

AND THE MAGNESIUM PART?
Ah yes, that bit. Using the known figures of relative usage between Calcium and Magnesium on average it can be shown that for each 147g of CaCl2-2H2O we are adding we need to add 34g of MgCl2-6H2O. This can actually be simply added to the same 2L mix as the CaCl2-2H2O.

That figure is actually an average, and the best way of knowing what your tank is consuming is to measure it on a longer term basis and adjust the amount appropriately. For example, if your Mg is sinking relative to a stable Ca then increase the quantity in the mix.

One concern this raises is that we have fortified that mix with more Chloride than we are adding Sodium, and at this point in time this remains unresolved. Further investigation is being conducted as to the resolution of this. Simple solutions such as reducing the quantities of each to result in a balance of Na and Cl will throw out the Ca and HCO3 balance.

GETTING IT FROM THE MIX INTO THE TANK
So far we now have a number of containers with various mixes of chemicals in them allowing us to add calcium, carbonate and a balancing mix of NaCl-free salts. It would be totally feasible to perform the final step manually by measuring out a set amount on a very frequent basis and adding it too the tank, and then removing a carefully measured amount. The problem with this approach goes back to the quest for stability and easy of use. Building in manual processes should be avoided as they will always end up being put off until later.

So the best approach to take is to setup a means of automatically dosing the mixes and removing the excess tank water. There are a number of different products around which can do this; I use an Aquatronica for other tank automation so it makes sense to use the dosing pumps available for that. For standalone purposes GroTech do a triple dosing station which can be expanded up to eleven channels, which easily will cope with the demands of this process, and for GHL Profilux users a dosing pump is available for that as well.

Each of these devices are programmed in a different way, however they all will allow very small amounts to be added on a frequent basis rather than a small number of high amounts. This spreads the dosing evenly throughout the day keeping the levels stable rather than rising and falling. As the main consumption of Calcium and carbonates will be during the lit hours, the dosing can be restricted to that time.

It is advised to always dose into a location of high flow in order to mix the additive as quickly as possible, but do remember to avoid the situation where the feed line can become a source of siphoning from the tank into the mix containers and onto the floor. It is best to drip the mix in rather than having the feed ending under water.

With all of these devices setting the amount to be dosed is simply a case of entering it into the device, this is the good part with the Balling method, once the pumps are setup increasing the dosing rate is a very quick and easy job.

Finding Supplies
A number of chemicals are required to implement this method, fortunately now several companies are specifically packaging them up for this purpose along with the NaCl-Free salt.

Calcium Chloride-Dihydrate Balling salts
Sodium Bicarbonate Balling salts
Magnesium Chloride-Hexahydrate Balling salts
Magnesium Sulphate-Heptahydrate Balling salts
Chloride Free salts for Balling
Alternatives for the Chloride Free salts include:
Tropic Marin Pro-Special Mineral
Pries Special

When looking at the cost of the NaCl-Free salts do remember that they may appear expensive, but you are only buying the expensive parts of the salt and not buying the 70% common table salt part of a standard marine salt.

CONCLUSION
And that’s about it, the darker side on Calcium and Alk addition but well work delving into, as with Balling it’s simply a case up dialling up a higher addition if your consumption goes up (indicated by falling levels so keep testing) rather than having to fiddle with flow rates and the pH and alkalinity of effluent from a calcium reactor, or hitting the limits of addition using a Kalk stirrer.