• Most concentrated salt available
  • Batch specific guaranteed analysis
  • Enhanced buffering inhibits pH shift

salinity™ is a blend of salts specifically formulated for the reef aquarium that contains all essential major, minor, and trace components found in natural reef waters, but contains no toxic or non-essential components. Additionally, salinity™ is the most concentrated salt blend on the market. With a hydration level of <0.5% salinity™ will yield a greater volume of prepared saltwater at a salinity of 35‰ per unit of weight than any other salt mix currently on the market.

salinity™ is identical to the distribution of anions and cations found in Natural Sea Water (NSW). We have compiled data from all the oceans and seas on the Earth, and have targeted the midpoint of the range for each element. We guarantee to be within ± 5% of the midpoint.

At a salinity of 35‰, for calcium, magnesium, strontium, pH, and alkalinity we have the following targets and/or ranges (see right).

Target 422 mg/L, range 400–443 mg/L
Target 1336 mg/L, range 1269–1403 mg/L
Target 8.4 mg/L, range 8.0–8.8 mg/L
Range 8.4–8.6
Range 3.2–3.8 meq/L
  1. Mix salinity™ with dechlorinated tap or purified water. We recommend the use of a commercial dechlorinator like alpha™ to neutralize any tap water chlorine and/or chloramines. If source water quality is poor we recommend purification with a Seachem Pinnacle™ RO/DI system. To prepare small quantities, add 36 grams per 1 liter of water. [This is a little less than 1/2 cup of salt per US gallon of water. For 15 gallons use 7 cups of salinity™.]
  2. Stir well to ensure a good mix. Although the salinity™ solution may be used immediately, we suggest mixing for approximately 24 hours to achieve oxygen/carbon dioxide equilibrium.
  3. Measure the salinity. We recommend a salinity of 35‰. This will be a temperature compensated SG (specific gravity) value of 1.026. If you are using uncorrected SG values (H) then the following formula will yield a value for S (salinity) accurate to within 1%:
  4. S = [0.3348 * T] + [1325 * H] - 1330.4525 (calibrated at 15.56 °C (60 °F))

    S = [0.2211 * T] + [1325 * H] - 1330.4525 (calibrated at 25 °C (77 °F))

    where S is the salinity in parts per thousand; T is temperature in degrees centigrade (range of 13-30 °C); and H is the uncorrected hydrometer reading. If you don't mind an error on the order of ±3%, simply use the following table:

    If the water temperature is: cal.@ 15.56 °C cal.@ 25 °C
    degrees C degrees F then target H= then target H=
    13 - 15 55 - 59 1.027 1.029
    16 - 19 60 - 66 1.026 1.028
    20 - 23 67 - 73 1.025 1.027
    24 - 27 74 - 81 1.024 1.026
    28 - 30 82 - 86 1.023 1.025
  5. Adjust salt level accordingly. If salinity is too low, then add more salinity™. If too high, add more water.
  6. Change 20% of aquarium water every two weeks (or as necessary) to maintain optimum water quality.
  7. USAGE NOTE: NEVER mix salt in an aquarium containing livestock. Transfer livestock to the aquarium AFTER salt is completely mixed and specific gravity has been adjusted. Use Seachem's Stability® to avoid "new tank syndrome" and to prevent unnecessary livestock losses in a new system.

Every bucket of salinity™ comes with a laboratory tested*, batch specific guaranteed analysis. We guarantee that salinity™ will have a guaranteed analysis that falls within the ranges below.

(* EPA Standard Method 6010)

NSW Min Max
pH 8.5 8.4 8.6
Alkalinity 3.5 meq/L 3.2 meq/L 3.8 meq/L
Calcium 422 400 443
Magnesium 1,336 1,269 1,403
Strontium 8.4 8.0 8.8
Bicarbonate 214 208 220
Borate 15 14.5 15.5
Bromide 65 63 67
Chloride 19,000 18,430 19,570
Iodide 0.06 0.0582 0.0618
Sulfate 2,655 2,575 2,735
Potassium 380 369 391
Sodium 10,500 10,185 10,815
Cobalt 0.0004 0.00039 0.00041
Copper 0.0003 0.00029 0.00031
Iron 0.01 0.0097 0.0103
Manganese 0.002 0.00194 0.00206
Molybdenum 0.01 0.0097 0.0103
Rubidium 0.12 0.1164 0.1236
Zinc 0.01 0.0097 0.0103

What's in your bucket?

To view the full lab analysis for your batch of salinity™ simply enter the lot# from the Guaranteed Analysis label (include all digits, e.g. "12345.00"). (This feature is only available for lots 48910.00 and greater)

When I mix salinity salt in my water barrel using a pump and a heater I get cloudy water. What is happening?

A: Because of the mineral content in salinity, it is possible to get some precipitant in the bottom of the mixing container. The residue that is left in the container is a direct result of a few things:

1. The highly concentrated materials used in the salt
2. Letting it mix too long/ or at a speed that is too rapid
3. A natural occurrence when mixing a high quality salt

When mixing this salt, we have found that 24 hours or less is ideal (more specifically 6-10 hours is best). The longer you let the salt mix, the more CO2 it will take on and the more precipitation you will encounter. CO2 --> water --> carbonic acid --> bicarbonates/carbonates. Mixing the salt for more than 24 hours can cause a decrease in alkalinity and pH, resulting in a precipitation of calcium and carbonates. When we mix it here at Seachem, we mix it in 50 gallon drums with one power head at room temperature (22-25 degrees Centigrade). There is no need to use a heater or multiple power heads. As a matter of fact, we do not recommend using a heater or powerful circulation when mixing Salinity. Typically the water is clear within a few hours but sometimes we have to use it within an hour of mixing, when it is still cloudy. This cloudiness clears rapidly once introduced to the tank, generally within 30 minutes, and will not cause any harm to the inhabitants. Furthermore, cloudiness seems to persist more with buckets that have calcium and alkalinity levels on the higher end of the range. This is really inevitable when you have such high levels of those particular components. I would recommend that you check the strength of the pump and reduce it if necessary, and to hold off on using the heater until the mixing process is complete as the heated water will create higher likelihood of precipitation.

I am mixing my saltwater to 1.025 specific gravity. Your label guarantees 410 mg/L for calcium but when I test, I only get 385 mg/L. Am I doing something wrong?

A: When our batch samples are sent off to the lab to be analyzed, the guaranteed values are at a salinity of 35 ppt. We do not use the measurement of specific gravity because this measurement is temperature dependent. While your specific gravity is 1.025, this does not mean that your salinity is up to 35 ppt. It is best to use a temperature compensated refractometer and measure in terms of ppt in order to achieve accurate parameters.

Can't find what you're looking for? Ask us a new question. One of the experts from our technical support staff will be happy to promptly respond. You can also call 888‑732‑0003 (Monday- Friday 9:00 AM - 5:00 PM EST) if you would like to speak directly with a technical support representative.

CAUTION: SALINITY™ IS NOT FOR HUMAN CONSUMPTION. KEEP OUT OF REACH OF CHILDREN. Contact in dry form may cause skin or eye irritation. In case of eye contact, completely flush eye(s) with cool water and seek medical attention.

7584 salinity 75 L
7582 salinity 450 L
7580 salinity 850 L

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