fermentation foam

I am brewing an American IPA. It has been in the primary for about 3 and a half days. Everything seems to be going well. I am just curious about the foam on top. It is only about a quarter inch thick. When I have seen other fermentation of similiar beers, there seemed to be a larger amount of foam. Is this bad that there is not a lot of foam? What does foam indicate? The airlock is active every two seconds so it seems like the yeast is pretty active and eating lots of that yummy sugar.
Thanks!
Greg

Is the temp pretty low?

Its lower than I would like...I am not monitoring the temp inside my closet but outside here it gets to 58 at night. So, in the closet its probably 63 or 64.

hbbend said:

Is the temp pretty low?

Click to expand...

Wow, all of the sudden it is getting more foam and today was a little more chilly than usual. But, I am guessing the colder temperatures are causing the yeast to eat more slowly therefore making the whole fermentation process a little slower.