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Calling Frederick/Firestone/Longmont/Johnstown residents!

Discussion in 'Tank Chemistry' started by whyamisofly, May 6, 2018.

  1. whyamisofly

    whyamisofly Prawn M.A.S.C Club Member

    Anyone in Frederick/Firestone/Longmont/Johnstown area home today that I could stop by and have you read the salinity of my water? I'm getting quite conflicting results between my Pinpont salinity monitor and my refractometer.

    Text me if you're available!
  2. whyamisofly

    whyamisofly Prawn M.A.S.C Club Member

  3. zombie

    zombie Tuna M.A.S.C Club Member

    Mix 3.24g of Morton's table salt to 100ml of RODI (total volume including salt, distilled is even better if you have it) or variation maintaining the same percentage by weight of salt. Place a few drops of that on your refractometer and instant calibration fluid for 1 cent.

    Sent from my SM-G935V using MASC mobile app
    TheRealChrisBrown likes this.
  4. whyamisofly

    whyamisofly Prawn M.A.S.C Club Member

    I don't have a scale that measures grams unfortunately
  5. zombie

    zombie Tuna M.A.S.C Club Member

    I would just make you some but in Utah for 2 weeks unfortunately.

    Sent from my SM-G935V using MASC mobile app
  6. TheRealChrisBrown

    TheRealChrisBrown Barracuda M.A.S.C Club Member

    And calibrate the refractometer to zero? Or 1.023, 1.025? Thanks for the tip!
  7. JZinCO

    JZinCO Copepod M.A.S.C Club Member

    If you're near fort Collins this week you can use my 35ppt standard
  8. zombie

    zombie Tuna M.A.S.C Club Member

    To 1.026 / 35ppt. Calibrating to zero is pointless and horrendously innacurate an can often be up to 2 ppt off compared to a proper calibration.

    Sent from my SM-G935V using MASC mobile app
  9. whyamisofly

    whyamisofly Prawn M.A.S.C Club Member

    I used the solution I have, but can't justify the results as it is several years old. I ordered a new bottle, but it won't be here until Wednesday. I'll be near animal attractions and Elite tomorrow, so I'll take enough water for both of them to test it for me.
  10. SynDen

    SynDen Shark Staff Member M.A.S.C Club Member M.A.S.C. B.O.D. M.A.S.C President M.A.S.C Webmaster

    In order to provide a standard for refractometers, a solution whose refractive index is similar to normal seawater is required. Seawater with S= 35 has a refractive index of 1.3394.1 Likewise, the refractive index of different sodium chloride solutions can be found in the scientific literature. My CRC Handbook of Chemistry and Physics (57th Edition, Page D-252)4 has such a table. That table has entries for 3.6 and 3.7 weight percent solutions of sodium chloride that span the value for normal seawater. Interpolating between these data points suggests that a solution of 3.65 weight percent sodium chloride has the same refractive index as S=35 seawater, and can be used as an appropriate standard (Table 2).
    This 3.65 weight percent sodium chloride solution can be made by dissolving 3.65 grams of sodium chloride in 96.35 grams (mL) of purified fresh water. That amount roughly corresponds to ¼ cup (73.1 g) of Morton's Iodized Salt dissolved into 2 liters (2000 g) of water (giving very slightly more than 2 L of total volume).
    For a rougher measurement in the absence of an accurate water volume or weight measurement:

    1. Measure ¼ cup of Morton's Iodized Salt (about 73.1 g)
    2. Add 1 teaspoon of salt (making about 79.3 g total salt)
    3. Measure the full volume of a plastic 2-L Coke or Diet Coke bottle filled with purified fresh water (about 2104.4 g)
    4. Dissolve the total salt (79.3 g) in the total water volume (2104 g) to make an approximately 3.65 weight percent solution of NaCl. The volume of this solution will be slightly larger than the Coke bottle, so dissolve it in another container."
    Last edited: May 6, 2018
  11. zombie

    zombie Tuna M.A.S.C Club Member

    Oops. Got conductivity and refractometer standard mixed up.

    Sent from my SM-G935V using MASC mobile app

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