Flushing is a topic of debate among growers on several forums.
AN and DM both have a 7 day flush built into their nute calc.
Having not flushed and flushed, I will choose to flush if I have time, but I can live without flushing if I haven't been using Sweet, or a Sulfer additive like mollasses.(never use Molasses in hydro)
If the nutes you are using stink when you open the bottle, then you need to flush. Having said that, if you have plenty of time and want connisour budz, raise the lights to 75%PAR and flush until the big fan leaves start to yellow. 10-14 days. Plain RO/distilled water, no pH adjustment.
I have put vanilla extract in the plain water flush, and you can smell it on the budz in two hours. If you want to add sugar to your budz, real maple syrup would be in them in a couple of hours, and then chop 'em and cure 'em. Don't leave this in your rez, add it just before the chop, after a long flush. AN Carbo Load is another option.
If you are running your nutes on a timer, then lengthen the "off" time to simulate drought conditions. Don't wilt them, but get close. This will cause the plants to drink hard when water becomes available. Also high VPD(low humidity) will cause rapid transpiration and aid in flushing.
Let us know what you decide to do so we can learn from your experience.
This is a good topic and should be explored.
Well Earl, I don't get the point of adding vanilla or any sugars to your flushing..........
however, flushing is very important to remove the ferts, especially the nitrogen as that one takes the longest to remove. If your crop goes unflushed and is full of nutes it will do two things. One it will burn/hurt the back of your throat. The other is that it will burn black ash and keep going out, not staying lit.
Clean buds burn nice smooth grey ash.
You meantioned AN's Carbo-load, which is not for the flushing cycle, but for previous to that to help beef up the buds. Two to three weeks before flushing it is recommended to add some P-K boosters of various kinds/brands to help fatten up the buds.
Another technique that helps to flush is to stop adding N one week before you start flushing, this way you clean out the more perdominat fert and leave a very smooth and tasty flavor.
Adding kool-aid and various urban myths will not help anything.