Originally Posted by petey_c
SilentT, I would gently move the "swamp thing" aside with a sanitized spoon and take a gravity reading. Three readings the same (every day/other day) and it's okay to bottle. Generally the krausen/swamp thing http://pl.wikipedia.org/wiki/Plik:Krausen.jpg
drops to the bottom. As you might've read here, three weeks in the primary and then three weeks in the bottle is a good rule of thumb.
shibao123, 20° C is a good fermentation temp. Some brews have a beginning fermentation that is very active and then slows down. No need to panic.
Don't forget that these are lagers...so fermentation times and temps will be different. 20C is much too warm for s lager yeast (and even for most ale yeasts in my opinion). Lagers should be fermented cool, then lagered even colder for several weeks, then bottled...so the standard ale schedule doesn't really apply.
As for taking a hydrometer sample...sanitize a measuring cup and scoop out about 1/2 a cup of beer. Fill your hydrometer tube and test it in there. Then drink the sample