As you can see in the screenshot below the Photos app is using 53,1 GB of the total Disk Storage, but also the Documents Folder has a .photoslibrary file of 50,34 GB. I tried deleting the file from the Documents folder, but then I neither had the photoslibrary in Documents nor any photos in the Photos app. Also, there was round about 100GB more of available storage (both storages of 53,1GB and 50,34GB were gone). When I copied the photoslibrary file back in the Documents Folder, the 100GB were there again (Same Phenomen as before).
What can I do to avoid having two Files using double of the needed storage?