CO2 Drop Checker Solution (4 dKH) - DYI

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Tyger
Posts: 121
Joined: Sat Dec 18, 2010 6:07 pm
Real Name: Michael
Location: Annapolis, MD

CO2 Drop Checker Solution (4 dKH) - DYI

Post by Tyger »

Greetings Folks,

Well, I think that one of the advantages to doing things yourself is that you end-up learning a lot. So, I went to Target and purchased Distilled Water (1 gallon) and A&H Baking Soda (NaHCO3-) and went to town. In the course of this project, I discovered that there is a lot of inaccurate information on the matter. Fortunately, I came-up on the low side... so I was able to continue to add small measured amounts of stock solution to the reference solution to obtain an approximate Reference Solution (≈4 dKH). Of course, I was left to wonder what went wrong. So, I made an effort to better understand things and here is what I found:
  • First, Baking Soda (NaHCO3-) is reactive with atmospheric moisture and the manufacturing process for consumer grade is not exacting and the soda contains imperfections.
  • Second, Baking Soda (NaHCO3-) can be heated though this alters the chemical composition as some part of the sodium bicarbonate would change into into sodium carbonate (changing the weights).
  • Third, CO3 is 71.44% of the mass in NaHCO3-
  • Fourth, in absence of precise lab grade measures and scales, one should use a digital scale accurate to at least two decimal places.
  • Fifth, KH Test Kits available to the consumer are not lab quality, which means the readings are not 100% spot-on. If the test kit works with 5ml (such as API), 10 ml allows KH to be measured in increments of 0.5 dKH rather than 1 dKH.
  • Sixth, unless one has access to the appropriate laboratory and equipment, Drop Check CO2 Reference Solutions are going to be approximations no matter what... which means, while we should seek to reduce factors contributing to error in every reasonable manner, the result is merely a close approximation.
With that said, I wanted to run my formula for my future home brews by the resident experts for a peer review of sorts:
  • Drop Checker Stock Solution (≈40 dKH):
    • Material & Ingredients
      • Distilled Water (1 Gallon) [purchased at Target]
      • Arm & Hammer Baking Soda [purchased at Target]
      • Digital Scale (MH-200 Professional Digital Pocket Scale)
      • Graduated Cycler or Measuring Cup (500 ml with 100 ml increments)
      • 2-3 Bottles [1 liter]
    • Prepare Equipment & Place:
      • Clean Equipment: use a bit of the Distilled Water to risen the bottles, graduated cyclinders, etc.,.
    • Cautionary Note:
      • Baking Soda (NaHCO3-) use a new box to minimize time of exposure to atmosphere (moisture), but do not heat.
    • Mixing Stock Solution
      • Stock Solution Bottle (1 liter/1000 mls): Fill with 1 liter of distilled water.
      • Add 1.00 g of Baking Soda (NaHCO3-) to the 1 liter of distilled water in stock solution bottle.
      • Yields a liter of Stock Solution (39.940 dKH or 713.335 ppm) remembering CO3 makes-up 71.44% of mass weight in Baking Soda (NaHCO3-) (cf., CNYKOI input 0.265 gallons and 1.000 grams).
  • Drop Checker Reference Solution (≈4 dKH):
    • Mixing Drop Checker Reference Solution (≈4 dKH)
      • Bottle #2 (1-liter) fill with 900 mls of distilled water
      • Add 100 ml of water from Stock Solution in Bottle #1 to Bottle #2
      • Yields 1-liter of CO2 Drop-Check Solution (3.994 dKH or 71.334 ppm) which is pretty close for home brew.
    • Option #1 (2 Reference Solution & 0 Stock Solution)
      • Pour 100 ml of Stock Solution into cup or graduated cycler and set aside.
      • Empty Bottle #1, Risen Throughly With Tap Water, Then Risen With Distilled Water (remember to leave at least 1 liter of distilled water).
      • Bottle #1 (1-liter) fill with 100 ml of stock solution that was poured into cup.
      • Add 900 ml of distilled water
      • Yields 1-liter of CO2 Drop-Check Solution (3.994 dKH or 71.334 ppm) which is pretty close for home brew.
    • Option #2 (Use 3rd 1-l Bottle or Use 1 2-l for Bottle #2)
      • 1 Gallon contains 3.79 liters. If you clean and risen efficiently though not sparingly, you have 3-liters with which to work.
      • Consequently, if you have 3 1-liter bottles, you can make 2 1-liter bottles of reference solution (4 dKH) and keep a 1-liter bottle of stock solution (40 dKH).
      • Although I have limited cabinet space and prefer to smaller bottles, Bottle #2 could be a 2-liter bottle, in which case the numbers must be doubled (i.e., fill with 1800 ml of distilled water and add 200 ml of the stock solution to yield 2-liters of CO2 Drop-Check Solution (3.994 dKH or 71.334 ppm).
Well, I think that works out right... comments, corrections, and thoughts?

~Tyger (Michael)~
~Tyger (Michael)~
Annapolis, MD
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