Help with flushing my Phototron!

[jmiah29]

Hello there,
I am new to the site and am seeking advice on how to flush my phototron.
It just started nutrient burn by the tips of the leaves, ppm's too high. It is on automatic watering with plain balanced spring water, on 12-12 in the 4th week of bloom. buds look very healthy. Any advice thanks!:

 

[dillinjabreak]

I got a small wet dry vac and would just fill it up with Distilled water and then suck it all out with a tube I have going down to the bottom.
Do it a few times and get a good flush! Hope that helps!

 

[dillinjabreak]

SO I'm at week 20......yes, I said week 20. Obviously it's running behind, don't really know why.
Guess that it's the LED lights and it just takes longer to flower, etc.

Well, I want to harvest now. I have been flushing for 2.5 weeks and decided to leave the lights off for a few days to see if it pushed them all little more towards wrapping up the flowering. I read that some place and figured it couldn't hurt really. I could be wrong thou :/

Here are photos. Would LOVE for anyone to give feedback. I was going to harvest tonight, but am not totally sure.

If you look, the Trichomes are cloudy but not really Amber.
The Pestules are PURE WHITE..and apparently they should be turning

So my question is: Do they change more after you cut them down?
And should I harvest now or wait even a little longer?
The Plant life, not the buds, are dying as you can see in the photos which is normal.