this topic was addressed several times and I followed the instructions online. I deleted, deleted permanently and purged the histories. Upon doing so my available disk space went up from 30 to 200 Gb. But once I start running new jobs they stop with the error ´no space left on device´.
I followed the instructions in this entry: https://biostar.usegalaxy.org/p/24283/ But I dont know how to use these scripts. Why is the user interface so complicated? And why does the server show me free disk space if there isn´t any space left?