Inadequate Amt. Yeast?

Hi, pretty new to brewing, just made an all grain Belgian Strong Pale. OG was 1.072. Fermenting at about 73 degrees. Pitched a vial of Belgian Ale yeast, fermentation went off without a problem. Is this enough yeast pitched? It looks great, lots of krausen etc. just about 10 hrs later. Will it run out of steam? Will it generate enough new yeast to be sufficient? I have never brewed anything with a higher OG so just not sure. Thanks for any advice!

starters are recommended for liquid yeast, especially for a 1.072, but it sounds like it ran its course, underpitching shouldnt cause fermentation to stop prematurely, just start later.

Two things to consider:

Jamil's Pitching calculator - http://www.mrmalty.com/calc/calc.html

and, maybe more importantly...

Basic Brewing/BYO's article on pitching rates - http://***********/blogs/pitching-rate-experiment.html (take the time to read this, it's pretty interesting and might save you some time and money)