Help! Should I add some run-off?

[chhc10]

So I just got done with an all grain batch. It was a 6 gallon batch of Tasty's APA. The target OG was 1.056 and towards the end of the boil we calculated that we were coming in too high and our volume was a bit low. So we added some water to dilute. But, we ended up a bit too low 1.050.

I collected a liter of wort before the boil to use in a starter for another batch and have it sitting in a Erlenmeyer flask. I believe the gravity is around 1.060. I was thinking I could boil this up and cool it in an ice bath and pitch it into the fermenter to raise the OG.

What do you guys think? Is there a way to calculate how much I will need to raise the OG? I also have corn sugar and DME.

Thanks in advance! Im trying to so this in the next couple hours before the yeast starts going...

 

[TANSTAAFB]

You COULD boil up the wort, add some boiled sugar or DME, or you could JUST LEAVE IT ALONE!!!! That would be my suggestion as you only undershot by 5 points. I wouldn't screw with it, enjoy your slightly lower ABV beer, and chalk it up to a learning experience. Next time double check your volume and gravity readings.

 

[onthekeg]

I would have sparged more through the grain and boiled longer to get the final outcome. Adding water directly to the boil kettle will not help raise your final gravity. If your runnings are above 1.010, add them to the kettle and boil longer.
Things to try next time, I agree with TAN that you should just leave what you have alone.