whats wrong with this?

Hello everyone,

I have some concerns with one of my girls showing yellowing of the veins followed by rust spots. The last picture is another Plant showing this really strange "twoface" leaf. Its the only one on the whole plant, the rest looks healthy.

Help is really appreciated.

Strain super lemon haze
Medium soil mixed with 10%coco
ph6.5 / ppm1300 / runoff ph 6.3
2x600Watt hps
Watering 2-3times a week / feeding once a week
Flowering week 4
Temps night 18c° / day 25-27c° / Humidity 40-50%

Maybe a cal deficiency? I ll restart after this.

Check your leaves with a scope

That looks like broad mite damage

Thanks for your reply. I looked really closely, cant find any mites.

Yea looks like cal to me, they look healthy overall tho to

Thats calcium def