I'm worried about a brew that I am fermenting with Wyeast 1388 and had some questions about the yeast strain.
Little background info:
I brewed a Golden Ale this past saturday and got 5.5 gallons of wort with an OG of 1.082 which I chilled to 64 F. Mash temp was 148 for 90 minutes and I know that my thermometer is accurate.
I pitched a nice healthy starter of Wyeast 1388 that had been crashed in the fridge for about 8-9 hours. This was around 9 PM.
Then next morning, about 10 hours later I had some noticeable yeast activity, and full blown fermentation by sunday night with an inch of krausen and a temp of 70 F. Last night (monday) I noticed that the krausen was starting to fall, and today when I got home from work the krausen had completely fallen back into the beer leaving only clusters of small bubbles on the surface. The airlock is still bubbling every 2-3 seconds, but the gravity is only at 1.042, which places it at the halfway mark.
The current fermenting tmep is about 80 F.
Is this normal to have such rapid rise and fall of the krausen with this yeast or am I in trouble because the krausen is done after only 3 days of fermentation? I was planning on adding some sugar to dry the beer out after the krausen fell, but I feel like there are still way too many malt sugars left to toss in some cane sugar.