I'm new to the world of homebrewing, having completed 2 batches. Both batches have been 'recipe in a box' kind of beers from Brewer's Best. The first was an Imperial Nut Brown Ale, and the second was an Irish Stout. In both cases, the beer was bottled for the carbonation process.
The first beer was still flat after 3 weeks, and after agitating them and waiting an additional 2 weeks the carbonation was fine. The second was great (carbonation-wise) after 3 weeks.
The first beer came out to about 1.5% below the expected ABV (came out to ~5%, when expecting a ~6.5% ABV), and the second one came to a disappointing 3%, when it was supposed to be 4.5 - 5%.
The first one tasted pretty good, but still had a small water aftertaste almost separate if that makes any sense (consumed anywhere from 5 weeks to 4 months after bottling). The second beer was horrible. By the time the beers were consumed (~5 weeks after bottling), they were over-carbonated and it felt like half your drink was an Irish Stout and the other half was tonic (a friend involved in the brewing process swears that he tastes the StarSan, but I didn't).
So the question is, why does my beer have a separate water aftertaste?
If you need additional information, please comment.