dam eagleclaw

hello comrads. so my ladies are 6 week veg and 5.5 weeks into bud. buds look marvelous.did 4 feedings {starting at first week of bud}there in 3 quart pots with mg soil. flushed them 2 weeks ago no nutes since i thought the eagleclaw spindly cola leaves would improve but to no avail. leaves continue to yellow and have rust spots now tips r slightly dead. but they still have good leaves and great buds.... do u think i should start slight nutes again?? because they need nutes?? or when i flushed them in the mg soil does that worsen cuz of the plant food in mg soil. hopeing they make it another few weeks till harvest. and how to tell harvest time with micrscope??? thank you , newbie p.s. my room has 600 hps good ventalation

Lay off the nutes for a while. you may have salt block/nute lockout due to rootbound plants. Remove 2/3 upper soil(including air roots), soak and wash main rootball in pH 6.5 water(to remove salt blockage). Do not molest main rootball - don't break it up or wash off it's soil. Repot plant in bigger pot with a little coco coir on the bottom. Add new soil then water and leave it for a few days. The plants may get a little greener and start growing more foliage. This is normal as the plant works out the Nitrogen excess in it's system.