Hi Jalbit,
1-2 weeks. When your thc looks mily and not crystal anymore :)
Also, how warm is it in your tent and how high are your lamps hanging?
Your buds are toxtailing, indicating that your room is too hot and your lamps are a little bit to high :)
Good luck growing :)
Start with "flushing" and harvest in around 10 days time is my opinion.
No need to drown your plant, just give plain water, no nutrients, at normal intervals and in normal amounts, this is all that is needed for a "flush".