Have you guys had any experience using Munton's Carb Tabs? I used plain ol' sugar up until about a half dozen brews ago. It says 3 for medium, 4 for normal, and 5 tabs for high carbonation (per 12 ounce bottle). I've used mostly 4 tabs per bottle on 8%-9%+ ABV beers and gotten good carbonation levels. I just brewed a batch that's just around / below 8% (an oatmeal brown ale), I used 4 tabs, and for some reason, after a month, it's almost flat. It has barely any carbonation. Would you guys recommend saving it for another month and trying it, or maybe cracking each bottle open and sprinkling some sugar in? I doubt the yeast got tired, I almost always put 2 of the Wyeast big packs in, which is more than enough. The beer tastes fine, so I don't think it was infected by anything.
