WineCalc app VS Charts

[topkeg]

I'm preparing to add some sugar to my newly started batch of Loquat wine to push up the SG. So I downloaded some handy charts to help with the sugar amounts. In doing this I ran across the "WineCalc" app for my phone. Seems to be a pretty neat app, but when I use the "chart", to get from 1.040SG to 1.095SG it calculates to 5.6LBS of sugar. When using the WineCalc app, it calculates to 7.2LBS. That's a BIG difference. ANy thoughts would be appreciated. Of course the traditional way of some sugar, take a reading, some sugar, take a reading is still the best. But at least having a fairly reliable target would be nice.

here is the chart I'm referring to:

URL="https://beer-wine.com/blog/how-to-adjust-specific-gravity/"]https://beer-wine.com/blog/how-to-adjust-specific-gravity/[/URL]

The APP:

 

[sour_grapes]

Fermcalc also says 7.2 lbs.

Is it possible you are not using the chart correctly? This is just a guess, but my guess is that your chart value was based on a FINAL volume of 5 gallons. Fermcalc says that this would require adding 6.4 lbs to 4.5 gallons of water. Still not the same value as you derived from your chart, but closer...

 

[sour_grapes]

I just looked at that chart you posted, and read its instructions. It cannot make sense in detail, because the instructions implicitly ignore any change in volume due to the sugar addition. I'd go with WineCalc/Fermcalc's result, although, as you point out, it would be prudent to "sneak up" on 1.095 by adding a bit less than the indicated amount at first.