Help with brix

[shoebiedoo]

I started 2 batches of Brehm frozen grapes a few days ago, a 2018 Sryah and a 2013 Zinfandel.
day 3 into fermenting and I'm getting confused.
The Zin was adjusted to 24 brix prior to pitching the Yeast (D254) the fermentation kicked in yesterday and today it appears to be going strong. When I measured the brix this morning using a Hydrometer it read 20. This evening it appears to have GONE UP??????? to 25. I know this is impossible so I got the refractometer and got the same reading. had anyone seen anything like this before???
But sinse I got the "Refracto" out I thought I'd checkout the Syrah. It measured 14.6 (corrected) and 17 with the Hydrometer? Is this common to see this big of a difference between the 2. Which should I trust? Does it even matter LOL

Thanks guys

Shoebiedoo

 

[salcoco]

the Zin went up because you had more sugar released from the grape.

when you mean adjusted on the refractometer do you mean the temp adjustment or alcohol adjustment. actual; makes no difference which adjustment should not be this far apart. did you calibrate the refractometer?

 

[shoebiedoo]

the Zin went up because you had more sugar released from the grape.

when you mean adjusted on the refractometer do you mean the temp adjustment or alcohol adjustment. actual; makes no difference which adjustment should not be this far apart. did you calibrate the refractometer?

Calibrated and correted for alcohol. I used the spreadsheet on. Morewines website.
And going from 24 brix to 20 then up to 25 seems like a lot!!!!! I hope I'm not going to end up with 20 galling of Port LOK

 

[salcoco]

I am wondering if the hydrometer is reading correctly. was the initial measurement all with the hydrometer? might want to check its calibration

 

[shoebiedoo]

I am wondering if the hydrometer is reading correctly. was the initial measurement all with the hydrometer? might want to check its calibration

I used the refractometer at 1st. The 20 brix this morning was hydrometer

 

[shoebiedoo]

I used the refractometer at 1st. The 20 brix this morning was hydrometer

 

[salcoco]

I question the hydrometer. try a different one of see if ti calibrates against water.

 

[Rice_Guy]

The CO2 which yeast produce will stick to a glass hydrometer. Readings during fermentation are notorious for being off.

To get a true reading you could heat 100 ml in a microwave for a minute, stir to remove CO2, then cool and rerun. ,,, some folks just spin the hydrometer and say good enough.

 

[shoebiedoo]

Well, SALCOCO was on the right track. This was a 50gl fermentor and had a very high brix. but I got Jittery after adding 2/3's of the calculated Acidulated water, after seeing m desired brix. needless to say all the wonderful sugars started fermenting my brix went up. Well, I went on a leap of faith and SLOWLY added the remaining water last night so we shall see how things read today. Thanks for all the imput

 

[shoebiedoo]

The CO2 which yeast produce will stick to a glass hydrometer. Readings during fermentation are notorious for being off.

To get a true reading you could heat 100 ml in a microwave for a minute, stir to remove CO2, then cool and rerun. ,,, some folks just spin the hydrometer and say good enough.

Yeah. Im learning that while fermenting is going on neither is much more then a WAG. I think the brix going up on the BRIX is what really threw me off.