I brewed last Sunday, chilled, pitched my starter and had held it at 65-67 ever since. Airlock activity is good, but the krausen is almost non-existent. I'm not too worried, I took a gravity reading after 4 days and its gone from 1.052 down to 1.020 so fermentation is active, I've just never experienced such a poor krausen. Normally its a couple of inches or out the blow off tube, not a thin blotchy layer of yeast.
Anyone else experienced this?