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Engineered Seawater Salt Pre-Mix for Research, Commercial, and other Professional Applications

C8R Spread Formul8x Reduced.bmp

Shown: Formul8x in Reef Blueprint packaging. L to R: Formul8x ASW, Formul8x Reef, Formul8x RSW. Commercial packaging options are available for users not requiring a shelf presentation.

The Formul8x series of engineered seawater pre-mix formulations yield economy and precision, two characteristics which are typically mutually-exclusive in engineered seawater salt blends.  All Formul8x formulations require that the user supply their own sodium chloride meeting the following requirements: ≥99.5% purity; free of additives.  In North America, three commonly available examples are: Morton Purex (not TFC Purex, which contains Sodium ferrocyanide as an anti-caking agent); Cargill Hi-Grade Granulated; U.S. Salt Superior General Purpose.  These products meet Food Chemical Codex (FCC) standards, and are available from regional suppliers in pallet quantities of 49 bags (50 lbs. each).

Per unit mass, sodium chloride generally comprises >68% of engineered seawater salt.  Resultantly, sodium chloride accounts for >68% of the cost of freight attributable to finished product.  If a local supplier of suitable material can be located, then it is economically advantageous for a user to source an appropriate sodium chloride locally and obtain the remaining components of a seawater salt blend from Captiv8 Aquaculture, rather than have us prepare and ship a complete seawater salt blend which will cost appreciably more per unit mass (particularly as the distance between our production facility and the destination increases).  The same can be said of any producer of a complete seawater salt blend.  The widespread distribution of the aforementioned salt products throughout North America, and products of equivalent quality elsewhere on the planet, make this approach to engineered seawater quite economical.  We gladly source the sodium chloride for users unable to do so.

As an aside, the procedure to preparing a complete seawater analog with Formul8x is exceedingly simple: Partially fill a mixing vessel with purified water; add an appropriate mass of one of the aforementioned (or equivalent) sodium chloride products; add the appropriate amounts of Components 2, 3, and 4 (included in the pre-mix) to the vessel as directed; continue to fill the mixing vessel with purified water to the appropriate final volume. Circulate the seawater solution until the solutes have dissolved completely and pH stabilizes.  Assuming accurate measurement of the NaCl, the consistency of the resulting seawater solution will exceed 99.5% from one batch of Formul8x to the next (ratios of components will remain approximately the same regardless of salinity).

The following statements are accurate assuming that the user employs one of the aforementioned sodium chloride products, or one of equivalent of greater purity, additive-free.

The precision of ionic values achieved, relative to the values that Captiv8 Aquaculture publishes for each respective formulation, are consistent and generally within 0.05%, with slight variances depending upon the actual mass of sodium chloride and volume of water, as well as the purity of both, employed by the user.  Formul8x formulations utilize >99.5% w/w anhydrous materials, with purity not less than that which conforms to FCC and/or USP grade for major components, and USP and/or ACS-Reagent grade for minor components.  Due to the purity of components utilized, all Formul8x variants mix to ≥99% clarity of purified water utilized in the seawater preparation.  Formul8x blends do not deposit residue on static surfaces, such as mixing vessels and pipes.  Recommended applications for Formul8x blends are: aquaculture; zoological displays; and scientific studies demanding the greatest purity of components and accuracy of ionic values, such as in lab sea surface temperature ​analysis and biotope reproduction.

As standard formulations, Captiv8 Aquaculture offers the following:

  • Formul8x ​ASW (Open ocean ionic values, S=35.2)

  • Formul8x Reef (Coral Growth-Intensive, formulated for aquaculture of zooxanthellate cnidarians, S=35.4).

  • Formul8x RSW (Red Sea ionic values, S=40.1)

  • Formul8x MSW (Mediterranean Sea ionic values, S=38.2)

  • Formul8x BSW (Black Sea ionic values, S=18.0)

Captiv8 Aquaculture also produces customized formulations within the Formul8x series.  Clientele may dictate that the formulation follows seawater composition as recorded by a specific researcher, collaborative team, or lab.  There are many such analyses published.  Published values generally reflect open ocean ionic composition (Arctic, Atlantic, Indian, Pacific, Southern Ocean, and marginal seas with ionic composition similar to open ocean values, herein collectively referred to as "average seawater").  Because the values for all ions tend to vary less than 2% (S=35) in these reports (even dating back to the 1960's), we do not feel that there is much practical difference in outcome of using one report vs another as a basis for an engineered seawater salt.  Be that as it may, we do not recommend any one single report to follow as a basis for reproducing average seawater chemistry.  Interested parties are directed to any appropriate peer-reviewed literature published within five years of this date which includes a comprehensive analysis of seawater using modern analytical methods, bearing in mind that the individual values published are sometimes a compilation of ion-specific analyses performed by individuals and labs.

If the client's objective is to have a formulation created which features an elevated or reduced concentration of one or more ions relative to their average seawater values, then the procedure is simply to provide us with the target values for those ions.  We are able to formulate and produce a blended salt which conforms to practically any requirements, with variance of ≤0.01%, assuming one degree of freedom (chloride in most cases).

Similarly, it is possible to formulate and produce an engineered seawater salt which accurately recreates the chemical composition of marginal seas with ionic values which do not conform to average seawater.  Examples are the Mediterranean Sea, Red Sea, and Black Sea.

Formulations may include or omit bromide, as dictated by the system design and absence or presence, respectively, of ozone injection.

Interested parties are provided a questionnaire which identifies the system requirements and user-specified ionic values.  A quotation is provided which reflects the total cost of production, using current material and labor costs.  Included is a Sigma-T reference table for the desired water temperature, as well as the volume of seawater which the formulation will produce at various salinity values.  The quotation is effective for thirty (30) days from the date of issue, unless otherwise specified.  The minimum order for production of a custom formulation is 20-lbs.  Note that the client is purchasing the blended product, not the formulation.  Formulations remain the express property of Captiv8 Aquaculture.

A general discussion on artificial seawater and aspects of sea salt composition considerations may be found here.


Notice: It is not possible to eliminate all risks associated with the use, handling, or storage of this product. Ineffectiveness, injury to crops and/or livestock, or other unintended consequences may result due to factors outside the control of Captiv8 Aquaculture or the seller. Buyer or user shall assume all such risks. For details, go to Terms and Conditions. Consult SDS before use.


Disclaimer: Captiv8 Aquaculture warrants that this product conforms to the description, and is reasonably fit for the purposes described, on its label. In no event shall Captiv8 Aquaculture or the seller be held liable for any incidental, consequential, or special damages, loss, or injury, including, without limiting, lost profits, resulting from the use or handling of this product. The exclusive remedy of the buyer or user for all claims shall be the return of the purchase price of this product. Express and implied warranties are disclaimed. Captiv8 Aquaculture does not authorize any agent or representative to make any other warranty, guarantee, or representation concerning this product.

For sale by Captiv8 Aquaculture and its authorized dealers, only.

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