Leaf & bud grow problem

[pagopendon]

hi, I'm new to this forum posting thing but after growing for 4 years I've managed to solve all my problems with google only, till now...

Got 50 seedlings sensiskunk under 6 hps lamps
earth soil, every 2 days i water with hp 6,5 & bio nuts.
they are in end of week 4 of flowering.

the fotos that are posted are only the bad plants, the others are growing normal or do not have a severe problem
tho they get the same nuts and water because i have a auto watering system.
the worst is that some of the buds just stop growing and the few hairs they have look burned/turning red..
for me the strangest thing is why do some have it worse then others and some of them don't have it...

would be nice if someone could help figuring out what my problem is..
or maybe someone got or had the same problem.

hope to hear something soon cuz i got the feeling if i don't act now, half my grow is gonna fail...

here the pics!

thanks!

 

[Chakow]

I wish my problem was as easy to diagnose as yours... get yourself some cal/mag.... make sure you PH your solution

 

[pagopendon]

Hmm.. Tnx for THE tip mate! Thing is, i don't grow for hobby and i have a very constant but safe (no risks in experimenting or trying to grow the biggest but and fuck up my harvest safe) and I try to have this up to 5 times a year... 4years with only miner problems and always solved it with no harvest loss. I pay my rent with it! I'm very pleased to hear you are such a pro but i really don't need your arrogance..
So, please if you can help me, tell me what you think I should do and especially why? So I can understand the problem and not just blindly pour nutrients into my plants cuz you say so...
You wouldn't either..
No disrespect, just want to be clear about it

 

[Fingernelm]

It looks like nutrient deficiency in my opinion. Some leaves have brown spots, some of them yellowing. So I would add nutrients. Please also check PH.

 

[OlderGrower]

Have you checked to see if your auto watering system is not partially restricted for this plant? In other words, is it flowing out at exactly the same rate and ppm as the others? I get you want a diagnosis and you want an explanation as to why you should follow the advice given to you, but more information would be helpful in giving you this information. You did not mention what type of medium you are using for the plants, pot sizes, do you PH after you add your nutrients and to what? How often do you test and calibrate your PH meter and or PPM meter.
How does your auto watering system work? Are you watering till pot has drainage or are you only watering a set specific volume every few days? Do you flush your plants.
No disrespect, just want to be clear about it