Different threshold for different filesystems alert in SAP

Hi Experts,

Need a help. We are receiving CCMS alerts for all filesystems. We have this set up using saphostagent.  We have one problem. Whenever we set a threshold for alert (like 90%) for any filesystem in RZ20. It gets reflected to all the filesystems.
But we have different filesystems. Some have 400 GIG space where even 90% is not a stage to worry and we can take time to clear space or to add space. But few filesystems have only few hundreds of MB and even 80% is alarming for such filesystems.

This way we need to set different thresholds for different filesystems. Please advise how is tha possible

Thanks
Varun