Starting week 1 on 18.12.23 with ca. 5 cm high seedlings.
In the following days I noticed very fast growing and thin tribes. My assumption is, that this happend to high temperatures during a failure of the control system (~30°C) or/and to high distance to the lamp (ca. 30 cm). I reacted with lowering the lamp and got the temperature under reliable control, which sucessfully stopped the growing in height.