Advanced guide to the Balling method

Guide to the Balling method (in-depth, for experts)

Sodium and chloride: what stays in the tank

With the Balling method, as well as calcium and bicarbonate ions, chloride and sodium ions are also added; if these are not used up, they slowly build up in the aquarium. The consequences are an ionic shift and a rise in salt content. To avoid this, you can use a sodium chloride-free sea salt, which it is advisable to dose in the same amounts as the Ca and KH solutions. The method also involves regular 10% water changes (I recommend every 10 days).

1. 1KH solution brings bicarbonate and sodium
2. 2Calcium solution brings calcium and chloride
3. 3NaCl-free salt prevents ionic imbalance, in the same amounts as Ca and KH
4. 4Consumption calcium and bicarbonate go to the corals
5. 5What builds up sodium and chloride, if not used up: ionic shift and more salt

Sodium and chloride build up slowly: that is why the guide adds NaCl-free salt and water changes.

Preparing the solutions

• Solution I (KH top-up): sodium bicarbonate (NaHCO3) 84 g/l of solution
• Solution II (Ca top-up): calcium chloride dihydrate (CaCl2) 74 g/l of solution
• Solution III (to prevent ionic imbalance): NaCl-free salt 25 g/l of solution
• Solution IV (Mg top-up): magnesium chloride hexahydrate (MgCl2) 35 g/l of solution.

1. 1I. KH top-up sodium bicarbonate, 84 g/l
2. 2II. Ca top-up calcium chloride dihydrate, 74 g/l
3. 3III. Ionic imbalance NaCl-free salt, 25 g/l
4. 4IV. Mg top-up magnesium chloride hexahydrate, 35 g/l
5. 5Dosing pumps one per solution, as in the basic guide
6. 6Tank each solution arrives through its own tube

These are the author's recipes: grams of salt per litre of solution.

Strontium, boron and potassium

Personally, besides the classic solutions listed above, I prepare solutions of potassium, boron and strontium that I also dose daily in minimal amounts:

• Strontium solution: strontium chloride hexahydrate 100 g/l of solution (in 450 litres I dose 1 ml a day for maintenance).
• Boron solution: bring the KH of the solution to 30 (to avoid precipitation), sodium tetraborate decahydrate 10 g/l of solution (in 450 litres I dose 3 ml a day for maintenance).
• Potassium solution: bring the KH of the solution to 30, potassium chloride 150 g/l of solution, potassium hydroxide 3 g/l of solution (in this case I dose 1 ml a day for maintenance).

The doses listed above are the ones I use in my tank: very low doses but constant over time, which each reefkeeper can change according to their needs and at their own risk (my advice: never overdo it).

1. 1Strontium strontium chloride hexahydrate
2. 2Boron sodium tetraborate decahydrate
3. 3Potassium potassium chloride and hydroxide (3 g/l)
4. 4KH at 30 in the boron solution, to avoid precipitation, and in the potassium one
5. 5The author's tank the doses are his: they are not a rule

Each drop in the drawing is one millilitre: doses that are very low but constant, to be adapted to your own tank and at your own risk.

How to prepare the solutions

To prepare the solutions, just as with water changes, you use a container (a bucket will do), one or more circulation pumps and a heater set to about 25 degrees; I recommend letting the solutions settle for a couple of hours, after which they can be used.

1. 1The container a bucket will do
2. 2Circulation pumps one or more
3. 3Heater set to about 25 degrees
4. 4Settling a couple of hours
5. 5The solution can be used once settled

It works like water changes: mix, heat, let it settle.

Author: Salvatore Riccardo

Sources

1. Gómez Batista M. et al. (2020). Intercomparison of four methods to estimate coral calcification under various environmental conditions. Biogeosciences 17: 887-899.
2. National Library of Medicine (2026). Sodium bicarbonate (CID 516892). PubChem.
3. National Library of Medicine (2026). Calcium chloride dihydrate (CID 6093260). PubChem.
4. NIOSH (2019). NIOSH Pocket Guide to Chemical Hazards: Potassium hydroxide. Centers for Disease Control and Prevention.
5. NIOSH (2019). NIOSH Pocket Guide to Chemical Hazards: Borates, tetra, sodium salts (Decahydrate). Centers for Disease Control and Prevention.