Last two photos show leaves on one plant that both...

I have the same problem many times in this grow stage when use Advanced Nutrients , Could be not right proportion of NP/K and cal/mag deficit , let em dry out a little and feed with 4ml Micro , 3 ml Grow and 2,5 ml Bloom + Cal Mag , they might need also better air circulation

Oyster shell by down to earth should help

I feed them all the same. Advanced Nutrients Grow/Bloom/Micro and B52 at this vege state and it is all pH- 6.5 I can add CalMag though next time, ty all

Its small magnesium issue with calcium lockout first fade caused/and ph problem Let them dry out and load right stuff to them You can add like 0.25-0.5 ml/L of calmag to your feed days. Feed a bit less, care about ph and all will be diamond, One looks like flowering, maybe just photo Adjust ph to 6.3-6.4 if you in soil after adding all nutrition's. Happy Growing !!!

I think they are lacking nutrients. Give them some more food when you feed them and it should sort itself out. I hope this helps.

It's a Potassium deficiency, add some K :)

Hi there To me it looks like a a calcium deficiency or possibly a Ph issue.. I would add some calmag and see how she goes, if so the lisa are damaged will stay that way but it will prevent it spreading to others Best of luck 🌱