2 weeks in flower got a MITTY big problem

AHYONE KNOW A GOOD AND SAFE FLUSH MIX, IM TWO WEEKS IN FLOWER AND I SEEM TO HAVE PICK UP SOME UN WANTED GEUSTS. I WAS THINKING OF A WATER , NEEM, AND H2O2 MIX SO I COULD CLEAN OUT THE PLANTER SURFACE AS WELL AS THE ROOTS AND MEDUIM. AND I THINK H202 WILL HELP IN MOULD AND PEST REMOVAL. I JUST DON'T KNOW THE PROPER MIX RATIO. I HAVE 3 LARGE FEMALES A W. WIDOW, BLUE MYSTIC AND BUBBLISOUS. I USE A TEN GALLON RES, AND FILL TO 8glns. I RE-FILL IT ABOUT EVERY 3-4 DAYS. I WAS THINKING OF MAYBE ONLY RUNNING THE FLUSH CONCENTRATE FOR 1 DAY. HERE ARE SOME PICS. IF ANYTHING ELSE LOOKS BAD PLEASE LET ME KNOW. THEY ALSO LOOK ALITTLE DROPPY TO ME, AND THEY ARE THINNING ALOT

try just flushing your soil with regular water and use 3x the amount that your pot can hold i.e. 1 gallon you would use 3 gallons of water to flush wait about 1-2 days to dry out your soil because it will be saturated and just do it over again for flowering this helps get the nute taste out of the buds

also it looks like you could use more phosphorous in your soil