Complete Screw up Beer

Well I made my first foray into all-grain this last week. Had quite a few things go wrong in the process. I was aiming to make the Chocolate Mint stout that is in the recipe database, but I completely hosed up my numbers for how much water to add. There is just shy of 12 lbs of grain in the recipe, and while doing the quick math I ended up using just shy of 5 gallons for the Mash, and 6 gallons for the sparge, on what is suppossed to be a 5.5 gallon batch.

Anyway Digital thermoter conked out on me, didn't stop working, just became wildly inaccurate. I ended up switching over to a meat thermometer that wasn't very clear on individual degrees, so my temps were close, but not great.

Anyway, realized that I had alot of extra wort boiling (8 gallons) when all is said and done, luckily I had 2 free fermenters. Rather than boiling for hours longer to get the water volume down (I'm doing this on my stove), I thought I must have read the quantity wrong to begin with, and would go from there. After getting temps down into pitching range with my chiller, I took a gravity reading and realized that I was way short. 1.025 range.

Well reazlizing this would make it come out weak, and probably taste funny, I figured I had to increase the gravity and add more fermentables. I happened to have a bottle of Organic Blue Agave syrup that hadn't been opened yet, that I had bought for backsweetening a hard lemonade. So I added that until I got a gravity reading just above 1.040. I added 4 gallons to each fermenter, and pitched the smack pack of yeast (Irish Ale) to one, and mixed back and forth between the two fermenters, to both aerate and mix the yeast. All this while cooking dinner for the kids, because the process took alot longer than I thought it would.

Fermentation took off like gang busters the next morning when I checked it, and finally settled down 3 days later.

Now my questions...

The most god awful smell was coming from the beer. I've read all about "Rhino farts", but this was closer to a rhino crapping in my basement. Almost a sour smell but not quite. Why would this be alot stronger smell than the extract 5 gallon batches I have done before, or is it just this strain of yeast?

What flavors could I expect to come from adding the blue agave syrup?

Would this still be classified as a "Stout"? It isn't straight Black, but the color of a very strong black tea.

I'd say the blue agave will probably give you a tequila-like flavor, as tequila is made from agave. What that will taste like in beer I couldn't tell you. It certainly won't be a stout though.

Well, its under-pitched on yeast, and I agree that tart agave juice is probably why it smells so wild.

Definitely dial in your brewing process, and avoid distractions. I'd say your water volumes were very miscalculated. You don't want to pick an arbitrary number of quarts to pounds...

Get some brewing software...I started with the free promash just to get my volumes figured out. It lets you input mashtun deadspace, and figures in your grain absorption, so you can end up with 6.5 to 7 gallons of wort to boil down for an hour.

also really handy for those 90 minute pils boils and their higher evaporation loss.