Foam = fermenting?

[Kyral210]

Ok, another schooboy question. If there is some foam on top of my brew (top fermenting ale yeast), does that mean fermentation is still undergoing and I should leave it longer?

 

[Tony]

Depends on how much foam really. I leave my brews in the secondary for up to two weeks sometimes (depending on circumstances) and there's usually a small amount even when complete. If there's a good blanket, I'd say its still fermenting...

The only way to be 100% sure is to take gravity readings - when they say the same for 2 or 3 days, it's finished!

 

Tony's right!
Your brew can still be fermenting without a trace of head.