k6sh
u/k6sh
Feed options
Hot
New
Top
View
Card
Compact
I measure the OG using four devices on each brew (one would be enough). A similar unit to yours from a different manufacturer, the basic ATC refractometer, and a hydrometer. The two refractometer measurements are very close, and the hydrometer (doesn't compensate for temperature changes automatically) is usually right there with them. The last device is a Tilt in the fermenter, which is probably the least accurate of all but still works pretty well to visualize how the fermentation is progressing. Final gravity measurements with the refractometer will require corrections ( https://www.brewersfriend.com/refractometer-calculator/ ), but I'm not sure I have complete confidence in the result, so I prefer the hydrometer as a source of truth with FG.
Example from my last brew of results from the two refractometers: https://imgur.com/a/oJ5tviT
In my original post I said the yeast was just under 5 months, but it was actually 164 days (a bit more than 5 months) from production until the first starter was made.
I used a few calculators, these two said zero percent viability:
and these two that reported 25% and 29% viability respectively:
I suspect ~35-40% viability was probably the case.
