Nute burn or PH issue?

Hey guys, i've been flowering these plants under hps for nearly 2 weeks i hit em up with quarter dose of bio thrive Bloom and big bud and they're reacting funny.

I have younger plants that i feed under CFL's and they're not burned like these ones...could anyone tell me what the issue is here, PH or Nutrient burns??

I need to buy a ph and ppm meter ASAP!! I had never seen my plants react so strongly to such a low dose of bloom nutes, they were totally fine 2 weeks ago before flower under hps.

Looks like my problem. I have asked if it is nute burn but no one has got back to me as off yet. To me mine and yours look like it is nute burn. The ones under the hps will suffer from drying out leaves due to the nute burn and make it worse due to added heat from light

it could be that your ph is off. either in soil or your water nutrient mix. if ph is off it will lock out nutrients so you try to fix it by adding more. it will make it so that one nutrient is locked out and others are taking up more. plants need a perfect balance of 16 nutrients. i just read an article about how magnesium affects the green chlorophyl and causes browing and yellowing of the leaves. everything is connected to each other so i bet its your ph. my ph was off and it caused severe problems. correct it or things will just get worse. i lost a big hindu because of that.

nutrient burn, can you see the real yellowish tops? That's one of the first symptoms on nute burn.. and see all the ends of your fan leaves and how all the tips are "burnt" looking.. I would do a flush

These types of problems are kinda tricky to tell cause your fan leaves can look like that with a def and also being overfed, so I look at the new growth and if its too yellow and burnt looking then most likely their overfed. Only other time I see plants looking like that is when they go into flowering and the tops yellow but it will usually go away in around 5 days

I really think it's a PH problem, i havent even fed it half dose, and i know ph being off renders nutrients unavaible, i have not tried to 'fix' it by adding more nutes.

Tomorrow im getting a ph meters and ppm meter.

Thanks for those who gave me some input. Peace

Doc

p.s Im also flushing them tomorrow.