Blätter verfärben sich komisch oder trocknen aus?

You are using too much and you are getting them rust spots, they are a form of giving too much for your plant to take up. It'll work better for your plant to mix it up. Split your nutrient down into 2 groups and give 1, 1 week and 1 the next or if you want to give them all in 1 week. Still split it up but give a good calmag watering in-between and make sure your soil is mostly clean of them nutrients before adding more different nutrients. It'll take a while for your plants to catch up. The rusting will only get worse. I'm dealing with the same thing. (Giving 1 plant to many different nutrients to work from. ) bring it down you'll find a plant with decent NPK ratios in the right range can be achieved with 2 to 3 nutrients some can even do a whole grow just using 1 nutrient at the same time. With a bit of calmag with the water to soft flush between nutrient feeds. Good Luck..