Stalled fermentation or high mash temp?

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ajm

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Hey guys unsure if I have a stalled fermentation, this is only my second brew so I have very limited experience. I went for a BIAB partial for this one.

Recipe

1.7kg Mangrove Jacks NZ Brewers Series Pale ale Kit + kit YEAST

3.5kg Golden Promise

0.15kg Crystal

Boiled for 60 mins and added extra hops during the last 10 min.

I used the 19L big W pot to mash the golden promise and a separate smaller one for the crystal.

I used around 14 L to mash in the Big W and then added the crystal and sparged with an extra 2L or so.

In the end the OG was 1067 after topped up to 21L, which seems pretty high so I might have had my mash temp a bit high (I put the big pot in the oven) In order to get OG up that high in brewers friend I need to increase my efficiency to 81%.

After pitching I didn’t have my heat pad set up for the first day so it was definitely under 18 C for that period but since then it’s been around 18C throughout.

Took my first reading 7 days after pitching and was at 1.020, I took a reading yesterday another 4 days later and it’s still at 1.020

Brewers friend is estimating FG of 1.015 when I input the M44 as the yeast .

Unsure what the kit yeast was but I think it might be the M44 US West Coast, I’ve heard it can have some trouble starting but normally finishes pretty low.

Basically I’m unsure if the fermentation has stalled or due to my potentially high mash temp and noobness this is as low as it’s gonna go.

I raised the temp to 20C after I took the second reading but unsure if I should get ready to bottle or pitch more yeast or try something else.
 

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The yeast is still with in its working range, if you look at your apparent attenuation (Change in gravity/OG, Just work in points) 67-20=47, 47/67=0.70 or 70% apparent attenuation. American ale will usually attenuate somewhere in the 75-77% range, some times a little dryer. Your software is predicting 77% apparent.
Mind you if you mashed too hot you will get a higher FG, not more extract just less fermentable wort (well unless its too hot then you will get less extract.
Reading between the lines I'm going to recommend you do a bit of study on the basics of mashing, John Palmers "How to Brew" is still on line and free, I think you will have a much better idea what's going on with a bit more basic knowledge.
When you finish that, have a look at Braukaiser if you want some more information.
Mark
 
Thanks for the response! I actually picked up how to brew and brewing classic styles so will be slowly making my way through both these books. The sample tasted decent so I'll probs cold crash it soon then bottle
 
The only way to be sure if your beer has attenuated properly is to do a forced ferment test. This will tell you the maximum attenuation your wort is capable of. Google it, but basically you take some wort, add a larger than normal dose of fresh yeast, put it on a stirplate and keep fit warm, and then measure the gravity are a couple of days/when fermentation is complete.
 

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