Help!!! Young leaves are dying (With Picture)

Strain: swiss cheese
solutuion ph: 5.8
Nutrients: Ferro Bloom A&B, Ferro enzymes, Ferro Bloom booster, and ferro Bio crop
Medium: 100% coco
Pot: 6L
E.C: 1.6
Tap water: E.C 0.5
Run off E.C: 1.4

Hi Guys, I might need your help here.
My plant is 6 weeks in flowering and is now showing necrosis on the young leaves (See picture).
It looks to me that it is a Mg deficiency and or K deficiency. Can anybody confirm or advise about other possible problem. + can abybody suggest the best solution to this issue.

Thanks

whats up with the blurry pics man?

sorry,took it from my mobile. Is now charging the camera...so better pics later

whats your temperature? looks like the damage is predominately towards the top of the plant.

temperature is 29 degrees celcius. i know it's a little high, but can it cause this kind of problem?