Dilution help?

One of my brews today came in at an i.g. of 1.065. I assume I had too much boiloff. Puzzling, because the boil times were the same. I was shooting for 1.054, and hit that with the wheat, but overshot with the ESB. I want to dilute down to target. I'm not sure how much water to add. I think I have about 4 gallons in each carboy for the ESB. I did a search looking for an old post on this, and didn't see it. Can someone point me to a suitable formula?

The water guidelines I was using suggested that I add some epsom salts, but I am out. Any reason I couldn't add those in when I add some diluting water to the carboys? I presume I'll be boiling the water, and might as well boil that too.

65 points times 4 gallons is 260 points.

You want to distribute 260 points into X number of gallons to get 54 points per gallon.

X * 54 = 260
X = 260 / 54
X = 4.81

So you need to add .81 gallons, or about 3 quarts and 8 ounces to each carboy.

Thanks for the help. I knew there was a formula, but couldnt' recall it at that point in the evening. Two brews in a day made a pretty long day on my current setup.

You already got your answer, but for the future an easy way to remember it is:
current SG * current volume = target SG * target volume

dcp27 said:

You already got your answer, but for the future an easy way to remember it is:
current SG * current volume = target SG * target volume

Click to expand...

Absolutely. I just can never memorize the formulas, so I just work them out every time I need them.