Can someone help me?:)I don't know what could be the problem

[jejukkoo]

I'm trying ebb & flow for the first time ...
everything worked great so far
but a few days ago the leaves started to turn yellow in the middle
the edge of one of them and the whole leaf of the other is yellow
and there are places where I see signs of too much nitrogen

there are places where the ends look like they are nutrient burn burnt but that is impossible under such ppm "i hope"

I write down information that is necessary for you and you, as experts, can help with this
thank you for being here, have a nice day

so:
-50 sativa 50 indica
-photoperiod
-4 week flower
-height 50cm
system :
ebb&flow
tank 60 liter
airpump 35 litres/min
water pump :
15 min run 45 min stop and again and again
use ro water
ph :5,8-6,2
EC : 800-880 the device only shows 88, but you have to multiply by ten

nute : hesi hydro bloom

Composition:​

• NPK 3 + 4 + 5​
• Nitrogen 3,0%​
• Phosphorus 3,9%​
• Potassium 5,1%​
• Other: magnesium, calcium, sulfate.​
• Trace elements: iron, manganese, zinc, copper, boron, and molybdenum.​
• Vitamins B1, B2, and B6.​
• Plant sugars.​
• Amino acids.​

+hesi phospour plus
4 ml cal
4 ml mg​

-root is Great nice white ...not rot

 

[SmokingWings]

everything worked great so far
but a few days ago the leaves started to turn yellow in the middle
the edge of one of them and the whole leaf of the other is yellow
and there are places where I see signs of too much nitrogen

I do not grow in ebb and flow, or any hydro for that matter. If it was a basic soil grow I would be thinking that it is a Nitrogen or Nitrogen & Potassium deficiency and not too much of either nutrient. In soil that sort of deficiency seems to become very common about a week to 2 weeks after the start of the first signs of flowering.

Maybe someone who is familiar with ebb and flow can help out.