One and half month before I just thought; if my plants have some nutrients, they may grow well.
So I bought a bottle of “Dünger” from “dm” and added water to dilute it.
The exposition showed that the proportion of nutrient and water must be 1:4.
Yes, I did it.
After one month later, one of the plants has gotten withering.
All of the lovely leaves have been dry up.
The poor plant had a serious catastrophe.
But the other plants were growing well, and they all were looked much healthier than before.
I couldn’t find out the reason.
It was really strange.
This phenomenon might cause of the osmotic pressure.
I also tried to give more H2O, but there was no significant change.
Fortunately this plant is still alive.
Look! It grows a new leaf in the middle.