This week went significantly better than the last two weeks. The plants seem to have recovered somewhat and are slowly becoming greener, appropriate for their age. The nutrient content in the water was slightly increased, but the overall water supply was slightly reduced. I noticed a slightly foul smell the previous week, so I didn't water the plants for three days to let the soil dry out. This noticeably helped the plants, so now I know not to forget and neglect the oxygen content in the soil. I now avoid moistening the soil in between and stick to fixed times. Usually, about half an hour to an hour after the light in the tent has come back on. Then I usually lift the pots to check the general weight of the pots and to compare the plants with each other. I noticed that one plant uses significantly less water than the other, so I can adjust the watering amount more individually. I would recommend this to everyone: lift the pots more often and check the weight. Additionally, I can advise not to keep the soil too moist, better to let it get a bit too dry rather than too wet all the time. The roots will thank you, and the flowers will grow better as a result.
@Moko420, Hey and Thank you! Yes i gave them everytime nutritions but i did not checked the ph Level. I gave them normal tap water, the water should have in my city round about a Ph level of 7,6