FG and refractometer help!!

So I went down to check on my IPA, brewed about 10 days ago and start my 3 readings to see if primary is complete. OG in brix was 17.8-18 and corrected out to 1.074-1.075, my reading a few min. ago was 8. Using a alcohol correction calculator online, who knows how accurate that is, gave me a FG of 1.005?!? I can't believe this is correct, that would mean a super dry finish and closer to 9% abv instead of the target 7.1% abv. What's going on here and can someone verify this with their calculator? I used safale-us05 for this batch and to my understanding it should attenuate to around 75%. What's going on here?

Using the calculators from Rooftop Brew and MoreBeer I calculated your ABV at 8.9%.

Wow, that is a bunch of sugar for an IPA. Sounds like you are using a refractometer and getting Brix readings from it. I agree that 17.9 %Brix would be about 1.074 OG. However, 8 %Brix final would give an FG more in the range of 1.024. I'm a hydrometer guy, not a refractometer user, so I am not an expert on how they work or how the results are to be interpreted. Can you check the SG with a hydrometer? Are you sure that the grain bill used would result in such a high OG? If my numbers are right, you are closer to 6 - 6.5 % ABV and 67% attenuation.

what the heck is going on here? I can't see it being that low of a gravity, I just don't understand the issue here. How can I go from 1.075ish down to 1.005 with that yeast? that's like 90+% so there is no way it can be that high.

my refractometer calculator shows the same thing, 1.006
what was your mash temp? did you add simple sugars?

US-05 goes about 84-88 AA on me. A couple threads I read, many people see this also.

I think that you have to make corrections for taking a reading using a refractometer after fermentation has begun.

Others will likely be able to point you to a website that will help you correct your brix post fermentation. I am just beginning to use my refractometer, but have read not to use it after fermentation, or if you do, you need to correct the reading somehow.

*OP, editing as it looks like you have already corrected the reading... sorry - this is what I get for not reading your whole post

As mentioned above, go to the MoreBeer site and download the free refractometer conversion calculator to SG. It corrects for the alcohol in the solution when using a refractometer.

Dr Malt

Dr Malt said:

As mentioned above, go to the MoreBeer site and download the free refractometer conversion calculator to SG. It corrects for the alcohol in the solution when using a refractometer.

Dr Malt

Click to expand...

Did that and if it's correct then my attenuation was way up, not wanting to risk it fermenting any more I transfered o secondary and started my dry hop. Will see what happens, hopefully this will help?