BIO-ACTIF SEA SALT - Sea salt with bio-active marine agents

Product description

The unique Tropic Marin® BIO-ACTIF SEA SALT contains naturally occurring marine biopolymers, which support the microbiological conditions in an aquarium and thus protect and enhance the growth of aquarium fauna.  

To this end, corals will exhibit their bright and vibrant colors in a natural way, while skeletal growth and/or the growth of stronger tissues are promoted. The reserves built up in this manner ensure that corals are more robust and less sensitive than otherwise. Fish also benefit from the bio-active substances by the formation of effective protection against damage to mucous membranes. Fish will exhibit their heightened sense of well-being by increased mating and reproduction activity.  

Tropic Marin® BIO-ACTIF SEA SALT is suitable for both beginners and advanced aquarists, and ensures stable conditions for all marine organisms at an alkalinity in the range of 8-9 °dH.


  • Contains natural bio-active marine substances with a protective and growth-promoting effect.
  • Develops a microbiological balance which stabilizes the water quality and supports the nutrient intake of invertebrates.
  • For reef tanks with carbon dosing and to create an ultra-low nutrient system.
  • To maintain the alkalinity in an 8-9 °dH range.
  • Fast and complete solubility in water.
  • Free of nitrates, phosphates and other unnatural enrichment additives.
  • Produced with pharmaceutically pure salts, without any nitrate or phosphate additives or other unnatural enrichments.
  • The ideal foundation for the care of even the most delicate fish and corals.
  • Highly compatible with all components of the Tropic Marin® BIO-ACTIF SYSTEM / BIO-ACTIF PROFESSIONAL Line.


Tropic Marin® BIO-ACTIF SEA SALT contains all major and trace elements as well as bio-active substances native to tropical sea-water contained in a natural formula.

Major Elements:

Calcium; Chlorine; Magnesium; Potassium; Sodium; Sulfur.

Trace Elements:

Aluminium; Antimony; Arsenic; Barium; Beryllium; Bismuth; Boron; Bromine; Cadmium; Caesium; Carbon; Cerium; Chromium; Cobalt; Copper; Dysprosium; Erbium; Europium; Fluorine; Gadolinium; Gallium; Germanium; Gold; Hafnium; Holmium; Indium; Iodine; Iridium; Iron; Lanthanum; Lead; Lithium; Lutetium; Manganese; Mercury; Molybdenum; Neodymium; Nickel; Niobium; Nitrogen; Osmium; Palladium; Platinum; Praseodymium; Rhenium; Rhodium; Rubidium; Ruthenium; Samarium; Scandium; Selenium; Silicon; Silver; Strontium; Tantalum; Tellurium; Terbium; Thallium; Thorium; Thulium; Tin; Titanium; Tungsten; Vanadium; Ytterbium; Yttrium; Zinc; Zirconium.


Application and dosage

To achieve a salinity level of 32-35 ‰ (psu), dissolve 35 ml (approx. 37-40 g/1.3-1.4 oz.) of Tropic Marin® BIO-ACTIF SEA SALT per litre or approximately ½ cup of Tropic Marin® BIO-ACTIF SEA SALT per US gallon water. Dissolve almost all of the salt in a clean container already filled with the full volume of RO/DI water at a temperature of 73-77°F / 23-25°C while circulating/stirring the water. Do not concentrate the mixture by adding the full amount of salt to a smaller amount of water.

Note: Always add the salt to the water, never the water to the salt.  Making a concentrated mixture will cause a calcium carbonate precipitate to form.

When you have added ALMOST all of the salt and the mixture is fully dissolved and clear, start measuring the specific gravity with a hydrometer or similar instrument.

Note: Slight cloudiness is normal at this stage and indicates that the bio-active substances are taking effect.

Keep adding small amounts of salt until the specific gravity is the value you desire. The specific gravity of the sea salt solution should range from 1.025 to 1.027 (at 73-77°F / 23-25°C) and the pH-value should be in the range of 8.0 – 8.4. If all parameters ​​are correct, the salt water is ready to use.

After setting up a new aquarium it takes a few weeks of water being circulated and correct lighting conditions to achieve the biologically stable environment required for the care and breeding of delicate marine organisms.

A weekly, partial water change, replacing 10 % of the total water volume with Tropic Marin® BIO-ACTIF SEA SALT , will help to maintain the water quality that your livestock needs for good health.

Dosing Calculator

Enter the volume of seawater that you wish to prepare here:
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We recommend the following dosage and a specific gravity (at 25 °C / 77 °F) of 1.025 - 1.027:
ml sea salt
cup(s) of sea salt

Other product recommendations

The very accurate, straightforward Tropic Marin® water tests KH/Alkalinity-Test Professional and the Calcium/Magnesium-Test Professional are suited for checking the quality of the water and the essential parameters.

We recommend the use of Tropic Marin® BIO-ACTIF SEA SALT with the other products of the Tropic Marin® BIO-ACTIF or BIO-ACTIF PROFESSIONAL LINE. These products are specifically designed for the Tropic Marin® BIO-ACTIF SYSTEM, which creates stable conditions in an ultra-low nutrient system in the aquarium – the ideal foundation for the care of even the most delicate fish and corals.