First Timer, Need

the lower fan leafs are starting to turn yellow and die and it has been flowering since jan 1 so its almost at 7 weeks, i just watered with a gallon of nutes yesterday so i am wondering if i should start flushing next watering or give it one more time of nutes? how long will it take all the fan leafs to die so i can harvest it?

You shouldn't judge the finish time of your plants by when the leaves fall off. Observing the trichomes is the most accurate way to monitor development. You can eyeball it, or spend $30 on a scope and get a really good view.

When and how long to flush is up to you, and depends on the strain's flowering-time.

In other words, it's trial and error.

fan leaves dying??..gallon of nutes?..keep it alive and buy a 30X pocket scope ..check the trichomes..if clear not ready ..if cloudy and turning rust color..take it!!..u want a bit of both cloudy/rust..this is the peak..also a good indicator is the pistols..u want 80% or better to be rusty..but as sk'mo said better to check trichomes....also flush 2-3 weeks b4 harvest..personally i don't drown them in strait water i just make my last 2-3 waterings strait water...

I like to flush about 5 days before I chop. 2-3 days after flushing I begin 24-36 hour period of darkness, then chop chop chop.

ok thanks and most of the trichromes are red now, i say about 70% or so, some nugs are at lik 80% but i was reading somewhere on here about some people dont flush because when you cure it all the chloroform and starchs gets turned into sugars so it doesnt taste like chemical, is this true or not?

ignore the hairsd. that isnt a way to harvest by. hairs can turn from to hot. its whole life its forming glucose, not just after harvest. yours sound over done or heat isses if that amber at 7 weeks already.
nobody can say what % of colours to cut at as we all preffer our own highs. what i like dont mean another will like. you need to pay attention to the trichs and cut at diff stages to see what high you want and for each strain will be diff times. amber is degraded thc to cbn.

http://www.cannabisculture.com/backissues/cc11/harvest.html

this will be helpful.

As far as knowing when to flush, unfortunatly if its your first time growing that particular strain its a guessing game, theres no way for anyone here to give you an exact time.
What you can do is take little samples every few days so you know when its at its peak, or when you get the high and feelign your seeking, so next time you will know.

Good luck.