New user questions

[Marhack]

Hi
Please let me know guys if I should open my bucket during fermentation? I'm making a lager from kit and after day my lid is sealed closed and now I can see lid going up becouse of gas pressure.

 

[clibit]

Just crack slightly to release pressure and shut again.

 

[Marhack]

And how long I should keep that in bucket?
4-5 or 5-7 days? I seen few options, and some guys on other forums keep it for 7 days for high fermentation and again for 7 days in next clean bucket for low fermentation before transferring lager to bottles