Sind meine Pflanzen Gesund trotz hohen EC ?

Yeah, probably locking something out -- looks extra lush even under grow lights (lush = dark green). Probably the cause of any blemishes - see a little interveinal chlorosis in spots. I wouldn't wildly run many extra gallons of water through it... just stick to normal irrigation with plain water - pH balanced, if necessary. just because some things are over-dosed, doesn't mean everything is. But when it gets overfed this much, the coinciding symptoms are often from lockut and not a physical deficiency. You'll know for sure over the coming weeks, LOL... as it draws back, keep an eye on it for other symtpoms... make sure those symptoms are not lockout before reacting to them. i'm in the midst of diluting rootzone, too. been giving 1/2 dose or less for a week at this point and the canopy is still a bit lush... just have to observe and react as you go. once i see a hint of fade in lower leaves, i'll jump back up to a modest level of fertilization.