White growth floating

Hi,
I have a white growth in the top of the fermenter, is it normal for my kind of brew? or is it a contamination?
This is a Lager, the yeasts i used are the W-34/70.

Here is a picture of the fermenter:
Pic1

Thanks!

 

That is probably contaminated. If it tastes and/or smells off, that should confirm it. Take a hydrometer sample and then taste it. If there's no off flavors, then it might just be that particular yeast (I haven't personally used it, but last time I used a lager yeast it did some unexpected stuff on top.) But the particular clumping of the formation on top is typical of certain types of pellicles that form in the case of excess oxygen + contamination.

 

Thanks for the answer and for introducing me to the word "pellicles", i searched over the internet and it looks a little different from the growth i'm having.
I left all the white stuff behind during the clarification process and bottled the rest, the taste of the brew is very good actually.
Will report in a month after i will open the first bottle

 

Keep those bottles somewhere safe, and check one early. If they are infected, they can turn into dangerous bottle bombs, exploding and sending shards of glass all the way across a room. Good luck.

 

Yes - it's a good idea to keep those in a rubbermaid tub or something. Bacteria or wild yeast can ferment things down farther than ale/lager yeast can, so it might continue fermenting in the bottles and kablooie!