flushing at last week ?

my plants are getting to finish.i will harvest one of them in a week.
i use biobizz full range and i will begin flush from tomorrow.
should i use plain water or water + molasses ( 1 tsp/ a gal. ) for flushing at last week ?

Somebody correct me if I'm wrong, but I think the way you want to do it is.. 2 weeks before harvest you flush by running 3x the pot size of water through it. If you have a 1 gal pot run 3 gals thrugh. Then after that you water with molasses.

i will give only plain water at last week and that is my flush technique .
Should i use plain water first and then water + molasses ?