Super low efficiency

[zephaniahsw]

Hey, I recently brewed an IPA with the following grain amounts:

11.5 Pale Ale Malt
1 Crystal 15L
.75 Munich Light
.75 Carapils
.25 Wheat

and got a post-boil OG of 1.042. Preboil volume was 6.5 gallons, mashed @154 for 1 hour with 1.5 qts/gal. Batch sparged with 3 gallons @ 180. I used an OG calculator and it said my PRE-boil should be 1.061, and Post-boil to be 1.079. I used a bit of lemon juice to bring water pH to ~6. This has never happened to me before, what is up?

 

[giraffe]

What was your mash PH? It should be in the 5.2-5.5 range. I assume 6 was your sparge water? Is your thermometer correct and calibrated? Other usual issues include improper grain crush, channeling in the grain bed, and sparging far too quickly.

 

[zephaniahsw]

The mash pH was 6, which is high, but I've seen better results than this with mash pH above 7. Thermometer is good, crush was good. Perhaps I sparged too quickly or with too little water, but is that enough to drop efficiency by half?