Fast Fermentation then stall.

[Schroedr26]

I am new to brewing. Just made an Oktoberfest (I know, it's spring) from a malt kit. Used Munton's dry yeast in a glass carboy. It started fermenting after about 12 hours or so. Had a nice krausen and air was pumping FAST out of the airlock. It lasted about 24 hours and completely quit. I had noticed that the yeast clumped some when I first added it. Is this normal? Should I add more yeast?

 

[Curtis2010]

OG? Temps? Current SG?

 

[Schroedr26]

OG 1.021 Currently at 1.018. It's been stored around 64-68 degrees.

 

[hopmonster2189]

You sure about the OG being 1.021? Need details on the recipe to help you

 

[Curtis2010]

You sure about the OG being 1.021? Need details on the recipe to help you

Yes, very low for your starting gravity...the yeasty beasties may have simply run out of food.