Boron (B) is an important macro-element in seawater, typically present at a concentration of around 4.5 mg/l. It exists mainly as boric acid and borate, and although its levels are lower than elements such as sodium, chloride and magnesium, it plays a vital role in maintaining a healthy reef.

Boron contributes directly to the alkalinity of seawater and helps regulate pH through the dynamic balance between boric acid and borate ion. This balance is essential for stabilizing pH, especially in reef aquariums where consistent water chemistry is essential.

Certain coral species such as Cladocora caespitosa show a strong pH dependence of boron isotope composition. This points to the role of boron in pH regulation and coral calcification processes, making it essential for healthy coral development and growth.

In the Reef Zlements blend classification, boron is listed as a Type C element, reflecting its unique handling requirements in marine aquariums.

To understand the scientific background of boron supplementation, we recommend consulting our detailed H2P methodology guide, available at the following link.

Dosage information:

20 ml of boric acid increases the boron content by 1 mg/l in 100 liters of aquarium water.