Black spots spreading // Need your help!

Appreciate your inputs! @Mrs_Larimar: Naa, Im using 2 units in total, wattage measured at 290W when at 100%. Maybe I misunderstood the input field, Ill look into that. I know, thats still quite heavy lighting for that footprint. But since the Cream Autos dont really show signs of any stress to me, I dont think its way over the top. I increased light distance to canopy to about 45-50cm now to have more diffused lighting overall (around 800 PPFD according to photone app). VPD is actually quite constant, apart from night time and when its raining heavily. Typical conditions range from 0.6 kPa (rain) to 1.0-1.4 kPa when dry weather. Im monitoring constantly and have an automated humidifier, but in case of heavy rain I would need a giant dehumidifier, probably even a big construction work type) as I live and grow in an old factory hall with 6m ceilings...LOL Nutrient problem should be solved, at least for Cream and Ztrawberriez. Plain water from now, as I want to take em out soon. That wont hurt the others too. @GMSgrows: I checked for septoria, but I couldnt see anything except those dark spots. No fungi IMO, at least it didnt spread anything visible in 100x magnification. Since Im using a mix of Allmix and Lightmix and supplement additional CalMag, Id place my bet on Manganese/ PH issues then. PH meter arrives within the next 2-3 days, Ill do tapwater check then and test a bit of runoff. Ill keep my diary updated!

after looking into your diary i was alittle shocked? are you using 4x the viparspectra XS 1500 in the space of 100cm? that would be way to much ihave been growing with those lights they are superstrong and 2 of the lights dimmed back to 70 percent and a good distance of at least 60 cm are way enough to grow super plants despite that your girls look good

short version, to much nutrients to much light, not enough water and VPD? is non existent but as you are close to be done, just accept not having beauty contest plants, overthink your next grow, in going easier with the factors reaching the optimal setup is much theoretical work, but if you reached it your plants look happy and green and grow like beauties