Gravity Question

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Hazelbrook NSW
Hi all

Into my third year of brewing;
  1. all grain brewing
  2. 35 litre Brewzilla
  3. allrounder (I ferment under pressure)
  4. Recently purchased RAPT Pill and RAPT controller (2nd brew using this)
I seem to have a lot if issues with my gravity. I've been using recipes online, I'm just brewing my 4th version of Naboo NEOPA aka Jedi Juice clone.

I have never been able to get the 1.070 OG that the recipe suggests, I always seem to end up around 1.060.

My concerns stem from this time around my pre gravity OG was 1.058 and my post boil OG is 1.061.

  • 7.25 KG fermentable
  • 22 litres of water
  • I mashed in at 68 degrees and mashed out at 78
  • I sparged for 30 minutes and had 29 litres in the kettle
  • boiled the wort for 90 minutes and cooled to 18 degrees prior to fermenting
Over 90 minutes I lose 6 litres (which is usual for me) and have 23.5 litres in the fermenter

Usually the beer comes ion at 6.5% with an FG of 1012, however I am concerned that the increase in gravity after boiling is on .003

Any suggested changes to my process would be appreciated.

I'm not 100% sure what the question is. The gravity will go up as the volume goes down as gravity is really just a way to determine the amount of extract (solids extracted from the grain) in the wort.

To get accurate results you need to be measuring volumes accurately (I notice a few 5L differences) and all readings need to be taken at the same temperature (normally 20oC) or adjusted for temperature.
There really is a lot wrong with your numbers. You are claiming around 82% efficiency into the kettle (unlikely on a Brewzilla. To get an OG of 1.070 you would need to be at 100% (that’s pre-boil). I suspect you arent getting what you think you are.

Measurement errors are among the most common. Check your volumes measurements very carefully, use a good hydrometer and at the right temperature. Check the temperature the Brewzilla is reporting.
Also before taking your sample give the wort a really good stir to help get a correct reading.
What kit are you measuring gravity with? Sounds like pre boil measurement off.
Always measure sample at same temp as calibration solution.
Dont let measuring device get hot.
'Scoop up' a sample from the bottom of kettle, to get a good sample
Measure 3 times and use average

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