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Question about OG, SG, etc.

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adamgm

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Greetings all,
finally got around to brewing my first batch tonight. I don't expect it to go well since I accidentally added water while trying to cool the mixture, and then dropped something in it afterwards.
Anyways, after transferring into my fermentation bucket, I was trying to make sense of the instructions asking for the OG (original gravity). I'm assuming this is just the specific gravity value at this stage? Is that right?

It was hard to read because of the foam, but it looked like I might have been around 1.04. Would adding more water bring this value up or down? According to my instructions, I needed to be between 1.049 and 1.053. However, I wasn't sure if added water would have brought me closer to this or made it worse.

Any help appreciated, thanks!
 
Hop on YouTube and check out a couple vids on taking the reading. A few simple pointers would be to pull a sample into your sample tube. Wait for bubbles to dissipate, and give it a spin. When it settles, take the reading. Any bubbles up against the hydrometer can throw off the reading.

Hope this helps.
 
If you don't have one already, a reading flask for you hydrometer is helpful. You can set it directly on a flat surface and I've found its easier to get a more accurate reading this way vs. whatever tube is usually included with kit hydrometers.
 
Northern Brewer makes a blue, hard foam ring about a 1/4" thick that fits on the bottom of the tube the hydrometer comes in to stabilize it for $1.79 http://www.northernbrewer.com/shop/brewing/brewing-equipment/testing-measuring/foam-hydrometer-stand-ring-blue.html. Then, when reading it, you see that water is 1.000. Then under that, 10, 20, 30, etc. And in between that, small lines that are read as 2, 4, 6, 8. So if it's 3 small lines below the "40" mark, it would be read as 1.046. Simple. When taken before the yeast is pitched, it's called OG, or Original Gravity. When taken when fermentation is done, it's Called FG, or Final Gravity.
 
Thanks for all the replies!

Adding water will lower your gravity. Was this an extract brew? From what I understand, adding top off water can throw off your OG reading and so long as you hit your target volume you should be okay. Don't forget to adjust your hydrometer reading for your wort temperature. There's a calculator you can use http://hbd.org/cgi-bin/recipator/recipator/hydrometer.html

It was an extract Brew, yes. Being new to this, I was going off a book I have and the instructions that come with the kit, nothing mentioned to adjust for the temperature unfortunately. In this scenario, I'm not sure it would have done me much good seeing as I had a hard time getting an accurate reading with the foam anyways.

If you don't have one already, a reading flask for you hydrometer is helpful. You can set it directly on a flat surface and I've found its easier to get a more accurate reading this way vs. whatever tube is usually included with kit hydrometers.

I don't think I have one, sounds like I need one. I did get a tube with a strange tiny house in the bottom, I'm not sure what it's for but it looks like it might be used to take a small sample of the mixture...

Northern Brewer makes a blue, hard foam ring about a 1/4" thick that fits on the bottom of the tube the hydrometer comes in to stabilize it for $1.79 http://www.northernbrewer.com/shop/brewing/brewing-equipment/testing-measuring/foam-hydrometer-stand-ring-blue.html. Then, when reading it, you see that water is 1.000. Then under that, 10, 20, 30, etc. And in between that, small lines that are read as 2, 4, 6, 8. So if it's 3 small lines below the "40" mark, it would be read as 1.046. Simple. When taken before the yeast is pitched, it's called OG, or Original Gravity. When taken when fermentation is done, it's Called FG, or Final Gravity.

I'll have to check out that ring. I understood how to physically read the hydrometer, I just couldn't see it well with the foam in the way... and I wasn't sure if I had too much water at that point or not enough. The instructions I had just told me to add it to ~ 5 gallons.
 
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