I bottled one batch of my cider with frozen apple juice concentrate as been discussed on this forum. It took 10 days for the soda bottle to build up pressure (it was a bit cold in my house). I got them sitting in a 170 degree water bath in coolers, and some of the bottle caps are leaking CO2. Did I overcarbonate? I drank one last night, and it still didn't seem that carbonated, so I put them in a warmer place today to finish up the carbonation. I used NB's O2 absorbing caps. I haven't used these caps before, but I didn't have any problems when I capped the bottles with them. Anyone else have this problem? No exploding bottles, but I certainly am leaving the cooler covers closed until the 30 minutes are up.