I brewed my beer and didn't notice a small leak in my wort chiller tube.* It wound up adding close to a gallon of water as it was cooling down the wort, dropping my OG dramatically. I missed my predicted OG before the leak. The beer was predicted to be 1.069 at the end and I was at 1.051.* Now after the leak my OG is at 1.038!!! (very upset) Is there anything I can add during the primary and secondary fermentation to boost the ABV as it ferments?* Can I add more Gold LME? I'm making a fruity pebbles beer and will be adding the cereal and a concentrated extract to the beer when the time comes for it.* Maybe the cereal will add a very small boost to the ABV. I'm wondering if I can heat up water, add the LME, cool it down to the wort temp and add it to it?
Welcome! Not a homebrewer myself but post here to get some help: http://www.beeradvocate.com/community/forums/homebrewing.8/
You can add sugar, honey, maple syrup, LME, orDME, to boost gravity. But, I would boil any of these ingredients before adding them. Any additions will obviously change your brew.
What you might have done, prior to pitching yeast, is add some malt extract to bring the gravity up. However, for a beer made with fruity pebbles, I think anything you do to dress it up is a waste of money and time. Just doesn't sound like something good. If you want fruity, play around with hops, some of which have natural fruity aromas, yeast, some of which produce natural fruity esters, and fruit, actual fruit. Well, that's my opinion, but maybe not helpful. Do as said above -- boil some extract in some water, cool, add to the fermenter if you have the headspace. Making up that kind of gravity with sugar and honey will lead to a very thin, unbeery beer. I get that you further diluted the beer because of the defect in your chiller, but why was your gravity off 18 points to begin with? That is huge.
A few thoughts: As @pweis909 said, your first concern should by why you missed your gravity by so much before your leak. Did lots of your malt extract caramelize on the bottom of your boil kettle? Are you sure that you got an accurate reading from your hydrometer? Did you follow your recipe correctly? Don't give up just because your OG dropped. You're not trying to brew a classic style, so 1.038 is not as disastrous as it would be if you were trying to brew, say, an American Stout. Even without adding additional sugars, you could definitely get a final product that is 4-4.5% ABV. The short answer here is yes. I add things like honey or candi syrup to the primary fermenter all the time. Sometimes I'm doing this to preserve delicate flavors in the sugar. Other times I'm trying to allow the yeast to get acclimated to a lower gravity wort before stressing them with more sugar. Regardless of why you're doing it, know that it is safe to do. I would sanitize some malt extract by boiling it for 10-15 minutes in a small amount of water, then add that a few days into your primary fermentation. The cereal probably will boost your ABV slightly. What are you trying to get out of the cereal specifically? Are you hoping for color or flavor?
You also could have brought your cooled wort back to a boil, and boiled off the extra water. Too late for that now though.
I'd be more concerned with the un-boiled water from the wort chiller introducing unwanted bugs into my brew. Correction I'd be the most concerned that I just brewed a beer with fruitty pebbles
