Spike Brewing 12.5 Conical Fermenter Giveaway - Enter Now!

Home Brew Forums > Home Brewing Beer > General Techniques > Reading a refractometer; clear line with distilled water; fuzzy line with beer

LinkBack Thread Tools
Old 04-16-2013, 03:23 PM   #21
Feedback Score: 6 reviews
Join Date: Apr 2012
Location: Cincinnati, Ohio
Posts: 1,948
Liked 178 Times on 139 Posts
Likes Given: 164


Yep. Agreed based on my testing on like 2 batches

Honestly, if I'm off by +/- 0.002 or 0.003 I'm not going to sweat it. Maybe 1% alcohol difference. I don't really care. I just wanted to know it was done and it was okay for that. And I will use it for pre-fermentation now that I got into BIAB.

mtnagel is offline
Reply With Quote Quick reply to this message
Old 04-19-2013, 08:58 AM   #22
Feedback Score: 0 reviews
Join Date: Sep 2011
Location: Berwyn Heights, MD
Posts: 102
Liked 2 Times on 2 Posts


Originally Posted by Yooper View Post
It's the alcohol. Alcohol changes the way light refracts and since that is what a refractometer reads, they are hard to read and inaccurate once fermentation occurs.

This x 2

Use a refractometer for OG and a hydrometer for FG. Alcohol content makes refractometers inaccurate.
MMBB is offline
Reply With Quote Quick reply to this message
Old 04-19-2013, 12:38 PM   #23
Feedback Score: 0 reviews
Join Date: Feb 2005
Location: Hubbardston, MA
Posts: 263
Liked 4 Times on 4 Posts
Likes Given: 2


Morebeer had a spreadsheet on their site to correct fermented refractometer samples and although I don't rely on my refractometer for FG readings the few times I tried it it was right on with my hydrometer sample. No blurry lines either.

bandt9299 is offline
Reply With Quote Quick reply to this message
Old 04-19-2013, 12:50 PM   #24
/bɪər nərd/
Feedback Score: 1 reviews
MalFet's Avatar
Join Date: May 2010
Location: NYC / Kathmandu
Posts: 8,181
Liked 1218 Times on 806 Posts
Likes Given: 555


Though alcohol will distort the reading, it shouldn't make it impossible to get a reading. With my refractometer, I have no problem getting a sharp line with wort, both before and after fermentation. If you're consistently getting a blurry line like this, it's likely caused by solids in the liquid that are preventing a good, clean contact between the stage and the plastic cover.


"Be excellent to each other." -Benjamin Franklin

MalFet is offline
Reply With Quote Quick reply to this message

Quick Reply
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Refractometer has extremely fuzzy line BobTheFourth Equipment/Sanitation 9 11-28-2012 01:10 AM
Gas Line/ beer line tubing replacement huskrfj Bottling/Kegging 0 11-26-2012 01:35 AM
Best Beer Line - No Glass Line, under $1/ft. BrewThruYou Bottling/Kegging 2 02-26-2012 09:13 PM
Using 1/4" braided line for beer line - ok? bmckee56 Bottling/Kegging 12 02-22-2009 06:40 AM
Colored vs. Clear gas line Prost! Bottling/Kegging 7 02-23-2006 08:09 PM