how long should the wort foam last for?

So I started my first brew last sat. I checked today and the once thick foam has almost entirely disapeared. Its been kept at about 18 degrees. When I open the bucket it smells really beery but sweet. It seems very quick for fermentation to have finished. I have a hydrometer to check SD but I thought I would ask you guys before I risk contaminating it. So is it good? Quick? Ruined etc? Any advice would be great. Thanks

Only way to tell is to check gravity. It can happen as fast as 3 or 4 days a lot of times. Even if it has reached FG, it still needs time to clean up.

There a lot of factors that determine how long the fermentation take and/or foam will last. Recipe, yeast and temperature among them. At 5 plus days there should be no concern about the foam having dissipated. It is unlikely that it is ruined and normal to smell sweet. The fermentation may not be finished yet. Now wait another couple of weeks then take gravity readings to determine that you have reached final gravity.

Unless you are incredibly thirsty, let it sit in the fermentor for a minimum of 2 weeks, preferably three. Making beer is about patience and the wait makes for a better and cleaner beer.

I was scanning through the threads quick and saw a thread about fart foam. I was intrigued. I'm now here and realize two things. One, there is no discussion of fart foam. Two, I should read slower when I'm tired.

Thanks a lot chaps, ill let you know how she turns out in a couple of weeks

Silly question from a newbie. How do you get a sample from a carboy to test? Really don't want to setup the siphon.

There's a special tool called a thief you can buy. You can also just use a sanitized turkey baster, if you've got one sitting around.

Don't pour the sample back in! Saving 1/3 a bottle isn't worth potentially infecting your whole batch.

Sanitize your hydrometer and just let it float in your beer. Spin the stem of the hydrometer when you let it float as that will shake off any bubbles stuck to it. Take your reading, remove hydrometer. Easy peasy.

Duhhhhh. Had not checked to see that it was long enough to reach wort and then be able to pull it back out. Sheesh. Thanks.