I rarely ask for help but I am hoping the community can assist with discovering where my problem lies with my final gravity. On 12/28/19 I brewed the following Irish Red; yes I am a freak about measuring so i can be predictable and repeatable:
6lbs Maris Otter
1lb Acid malt
4oz Roasted Barley
1.5oz EKG First Wort Hop
1/2 Whirlfloc @ 15min
1/2 tsp Wyeast Yeast Nutrient @ 15min
Dry English Ale yeast WLP007
Detroit Metro Huron pumping station Water 28Calcium, 10.4Magnesium, 4.5Sodium, 20Sulfate, 8.5Chloride, and 82Bicarbonate
I did a starter the night before with 1000ml of 1.040 wort on a stir plate. The next day I started the mash and it hit 160F so i immediately added ice to get it to 153F, which was close to my target. After 15min I measured the pH chilled to 60F and it was at 4.8 which was way below my target of 5.2. Beersmith said 1lb of acid malt would get it to 5.2? After 60min boil my SG was at 1.061. I then vorlaufed, drained and did a batch sparge. This hit 169F with a pH of 5.0. at a SG of 1.027. I ended up with a preboil volume of 6.75gallons and a 1.044PBG. After a 60 minute boil, then chill, i ended up at a 1.048OG with 6 gallons 5.5 gallons of which made it into the fermenter.
Fermentation started at 66F in my freezer w/controller. After fermentation slowed i moved it outside the freezer on 12/31/19 and noted a SG of 1.022. I left it to sit and do its thing until 1/9/20 when i discovered it was still at 66F and a SG of 1.022 so i moved it upstairs to warm it to 70F and performed a fast fermentation test with the 10g of Mango Jacks M42 i had on hand (expiration in June of this year) on a stir plate. After 48hrs i checked the test today and it was still at 1.022. Checked the beer now at 70F and it was still at a SG of 1.022. WLP007's attenuation is 70%-80% which would put me in estimated range of 1.014 - 1.009 so i feel like this beer's specific gravity should have gone lower.
So i understand that this is a process problem when i was brewing since the test revealed the same specific gravity. Could a screwed up pH really cause a problem?
Thanks for the assistance.