Error: Final Gravity is too low: -0.003 (Seltzer recipe)


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Jan 30, 2019
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Northwest Montana, USA
I'm getting various errors when trying to save a hard seltzer recipe I've made (I know, I know about seltzer opinions, anyway....) When saving the recipe in the editor (both Android-Chrome and Windows-Firefox), a pink error bar across the top says, "Error: Final Gravity is too low: -0/003". It also sometimes shows an error that says the final gravity must be a number. When this error happens, any changes to the recipe won't save. I believe that the error is caused if the final gravity is calculated to be less than 1.000.
I'm using only sugar as the fermentable, and yeast with attenuation set to 100%, brewhouse efficiency set to 100%, and a mash steeping step (for a short boil). Including hops or not doesn't get rid of the error.. I've brewed this before and achieved a 0.092 final gravity, but am unable to get the recipe editor to predict anything lower than 1.000 as a final gravity. Dry meads and other brews routinely come in under 1.000, so I'm wondering if this is a Brewer's Friend error or something that I'm not understanding about its use. Screen capture is attached.
If this is the wrong forum section to ask, please enlighten me. Thanks!
Unfortunately, the software does that when the FG is below 1.000. For mead, cider, sours, etc, it gives that error. We are looking into this now, and I will come up with an answer on the fix ASAP.
I'm still on this- I'll see if we can move it to a higher priority. I'm really sorry about this.
Found that if I hit this error, then add a few lbs of base malt, save, then delete the base malt, it will then let me save with the <= 0 FG.
Has anyone tried setting the yeast attenuation to something other than 100%? Say - 80-85%?
Let's add it to ticket #1758
Please check my error message (first post in this thread) and the one above.. They are two different messages, caused by possibly two different conditions. I have seen both. One being a divide by zero (must be number message above), and the other when the division results in a fg of less than one (fg is too low message). Where you are dividing to calculate that fg is where this is happening, when your dividend causes the fg to cross over from positive (>1.000 - no error) through 1.000 (NAN message) to negative (<1.000- fg too low message). That would explain the two error messages.
To add I also receive this error on most of my enzyme beers that zero out the gravity. I play with the attenuation but if I adjust any part of the recipe I have to go back to playing with the attenuation.