It has been mentioned but do not chase numbers. Most of it is not needed in a soil grow. So much of what is happening to provide the numbers is being taken care of by the microbes and other soil organisms. The life cycle of all that soil life is changing the numbers so many times the grower just ends up chasing them and getting nowhere.
The only number of concern is the pH of the water as it is being poured onto the soil.
You are in soil. Either in one of the ones from Dr Earth or now in ffof which is probably Fox Farms Ocean Forest. Both are considered to be decent soils.
Are the plants in the msg from the other day the same plants as in the first several messages from October 5th? Gotta ask since it has been just over 13 weeks ago.
Why are you doing a flush? The idea that a flush will be needed in a dirt & compost based soil has pretty much been proven wrong. Flushing hydroponic style grows is a different story.
By now you have had a chance to check out the chart that
@Sativa1970 provided. He mentioned potassium and it does look like a potassium shortage well underway. Since potassium is a mobile nutrient the plant is taking everything it can get from the older and larger fan leaves and moving it to the most recent of the growing leaves, stem and any flowers.
By the way, no one has asked yet, what is the line of fertilizers and nutrients that you are using? What is the feeding schedule including how often and how much of the fertilizers?