IPA fermentation not foaming as expected

I just made my first IPA 2 days ago. It is fermenting in my son of fermentation chiller at a steady 68F right now, but there's only about 1.5" of foam on top of the wort. The airlock is bubbling about once every 3-4 seconds. I thought there would be a lot more foam going on with this beer. Is 1.5" of foam in my 6 gallon carboy a sign of inactive yeast? I used Wyeast 1056 smack pack. I'll go into details about recipe and process if needed but if there are obvious causes of this issue (?) I'd like to know.

Rob

RDWHAHB. You're keeping it at a nice lower temp. You've just got a steady, but not explosive, fermentation. If you want a clean beer, you'll have it.

This is only my 2nd batch of brew so I don't know what to expect.

I neglected to mention the low OG (1.038). I used 6lb pale malt extract and 12 oz. crystal for the 5 gallon batch. The SG of the extract is 1.038. Maybe I need to bump up the extract a little.

thats typical of 1056. i've never had mor than like 2 1/2 inches of kraussen with that yeast. don't worry it will be fine

I get the same result when pitching only a activated smack pack directly into the wort, low krausen for a few days. I usually only get a huge krausen when I make up a starter for my large beers. After pitching a 2L 1056 starter into my DFH 60 clone last week, I woke up to beer all over my ceiling, walls, windows and carpet! I learnt my lesson that if you think you should attach a blowoff tube, then you had better attach the damn blowoff tube instead of going to bed.

not to keep repeating what everyone else said, but with the samck packs have never had a real high active ferment. I switched to the S-05 with my IPA's and great taste and highly active. as long as your having steady activity thru the airlock, you should be fine

I have an IPA that I brewed last week and have virtually no krausen after pitching a vial of White Labs yeast. Grant it it's a 7% beer and 9.5 gallons of it but I expected a slow start then vigorous fermentation. I think the oil in the hops maybe has an effect? Anyway the airlock is bubbling and I can see visibly that the planets are colliding in my wort but there is no krausen whatsoever.