Top sugar leaves with yellow tips

Week 4 onwards of flower makes the plant’s nutrient consumption increase tenfold, you need to increase feed including calmag if you are running SMD LED, lack of magnesium means the plant can’t produce chlorophyll which is what the plant uses to photosynthesise. Lack of magnesium also causes low terpenes, oils and cannabinoid content in the overall flower. That plant looks 5-6 weeks into flower already so one or two decent feeds then you’ll be looking to flush and harvest 👍🏻

I find if you take all the fan leaves off this tends to happen Aswell, you should always leave some on so you can see deficiencies before it attacks the sugar leaves too, because your trying to flush there is no leaves for it to pull the remaining nutrients out so next is the sugar leaves

Thank you!

my friend, asnoriu and i disagree on the flushing, so i'll say it in a different way... if you intended to flush at end of harvest, i think what he says is spot on. it's not quite ready for that yet, but close. So, if this was the intention, i would not waffle between feeding / not feeding until it is time to flush. don't overthink it. keep it simple. imo, flushing is a myth. i'd continue feeding till the end, because the plant is clearly not toxic and you must be rational in your fertilization choices so far. plants take up nutrients from the earth outside all the way until the end and you never hear people say outdoor weed tastees like chemicals... that stuff is placebo effect according to blind-taste tests anyway. either way, flushing the last 7-10 days won't have a severe impact in either case. if it makes you feel warm inside, do it. or, maybe you just want to compare and decide for yourself. all sorts of good reasons to try it. i just don't think any evidence supports the decades old hypothesis, and there's been plenty of time to prove correlation.

senescence starting - fall colors there. maybe a little light on nutes, but could also be grow lights making leaves look paler than they actually are. the overexposed pics always look lighter than reality. you look fairly far along in development of flowers, so i wouldn't overreact to it. if a leaf is fairly lush under normal lighting, i'd stay the course. A little damage at end is hard to avoid and some plants are touchier than others in senescence (end of life, related to 'senile' lol)

Should i flush her with Ph 7 water und feed her again?

Lack of K or too low ph. You still easy push her. Maybe last feed if soil or two max, depends does she drinks regularly. If all good with watering its hunger, if she is slow with uptake - most prob low ph went in.