I am in possession of at least half a dozen hydrometers, and almost all of them give different readings, even if the readings are converted to a standard temperature. There is little consistency, and I really don't know which one to use. Has anyone come across a hydrometer that provides reliable and more accurate readings than most? Thanks!
I wish you luck. In my experience, there's variation even with a particular model. And I've seen some expensive ones labeled as "precision" hydrometers that were pretty far off. The best hydrometer I have, because it actually reads 1.000 in distilled water at it's calibration temp of 68F, says it's a Brewmaster. I think it's the one at this link. At least it looks the same: https://brewmasterwholesale.com/products/fermentap-triple-scale-hydrometer.html But I've never bought anything directly from them, so it must have been from a LHBS or online homebrew supplier. I don't recall it being particularly expensive. I don't know if this will help you, because again, I've seen variation within hydrometers of the same type. If you're just trying to decide which of the hydrometers you already own should be the one to use, I'd recommend testing each one in distilled water at its calibration temp, and use the one that was closest to 1.000. And adjust your future readings by whatever amount it was off. If you don't have distilled water handy, tap water will do. It would have to be some crazy high TDS water to make a noticeable difference,
There is this Anton Paar unit: https://www.easydens.com/?gclid=Cj0...KMRhthHs7jKRFNfn2YyGn72ms-IG79xYaAhPhEALw_wcB That's not exactly the same one that I've used but it's similar and in the same price range.
Thanks, VikeMan This issue I have is not at 1.000 but at the higher gravities. Many of the ones I have do read distilled water fairly closely, but at the higher gravities, say 1.050, they can differ by as far as 3 or 4 points. I guess I could make up a calculated solution with DME, but even then, the calculations could be off by a couple of points, because DME is not all that consistent. I can look into the Brewmaster hydrometer.
Maybe try table sugar. 15.93 oz plus enough water to make one gallon of solution should come out to 1.046.
In my opinion, in the context of homebrewing, hydrometer precision is not that big of a deal. You're looking for a stable number to know when it's done fermenting, so you're good there. And it's the difference between OG and FG that's important in the final numbers, so, as long as you use the same instrument to measure both, you should be good (1.090 - 1.015 or 1.085-1.010 is still a difference of 0.075). That said, I believe everybody has at least a little OCD, so that may or may not be good enough for you.
Perhaps an even more important measurement is the temperature. Temperature gauges can be as far off, or even more, than hydrometers, and is much more important, especially regarding the mash temperature. Being 2 or 3 degress off in the mashing temperature can be very significant in terms of the resultant "dryness" or "sweetenss" of the resulting beer. However, it is far easier to check the relative reliability of a thermometer than a hydrometer. With a thermomenter, one only needs to check the freezing temperature and the boiling temperature (adjusted to elevation) to establish the general reliability of the thermometer used, although this doesn't necessarily imply that the mid-range temperatures are reliable But, other than using the lowest S.G. of distilled water at a specified temperature for one range of the scale, how can the reliability of a suitable mid, and practical upper range, be positively established in a hydrometer?
Yes, as I agreed to above. Assuming that sugar is fairly consistent in its properties and degree of purity, depending on the source. For example, if sugar is crystallized in distilled water, rather than in water containing many minerals, would there be a significant difference in S.G.? Also, if the sugar is not pure and contains other compounds resulting from the manufacture of the sugar, would that affect the resultant S.G. significantly? Sugar can contain various impurities, such as iron, magnesium, sand, ash constituents, bacteria, arabinose, xylose, galactose, ribose, fructose etc.
None of those things would affect the reading enough to notice, i.e. the difference would be smaller than a standard hydrometer (along with human eyes) can measure. You need a lot of accidental minerals to skew the reading. I once computed that you'd need approximately 2600 mg/l Total Dissolved Solids to skew gravity up by one point, and that's when adding minerals on top of the carbs' contribution. In your examples, where these dissolved solids would be simply replacing some of the sugar's weight, it would have even less impact.
