Came up short on the boil. Quick question.

My Beersmith brew sheet had some issues and I didn't catch it until the end. It said a post volume batch would be 3.12 gallons, but I entered it in as a 5 gallon batch. It was my first time with the new setup and was to distracted to catch it.

Either way, I would like to top off the volume. I was planning on boiling 1.5 gallons of water, tossing in a camden tablet and giving it an ice bath until it's at a safe temp to toss it in.

I'm a little mixed up on the 3.12 gallon thing, but you should be fine topping it off to 5 gallons, provided that the kit was intended to be a 5 gallon batch. You could even just top it off with some purified or distilled water if you wanted.

See in the Pre boil volume? It assumed my mash tun was 3 gallons. Huge brain fart on my part that I didn't register the volumes until it was too late. We topped off the boil pot a bit, but it still cooked off a lot.

I've topped off numerous times straight outta the tap. No problems to report, but if you are concerned go ahead and use bottled water.

It really is tough to ruin the beer, and at top up time the yeast is going in and will likely take hold, out performing anything else that might have made its way in there.

I'm assuming you sparged? Your last comment raised this question with me. For future reference, sparge with more water in the amount you were short this time, plus about 2qts. That extra is for what you will lose to trub.

Don't sweat it, I'm sure it will all work out.