Hello,   This is a known issue with SANHQ v3.1.   The next release due out this month will resolve that error.  There are several other threads here discussing this issue.  For now, disabling the alerts is best work around.   Regards,   Don 
I have recently been reconfiguring a client EQL group (1 PS6100, 1 PS4000).  As part of clean-up and modernizing of an older ESXi environment, VMs were storage vMotioned from 4000 to 6100 and the4000 reset, reconfigured and added to the "new" group started with the PS6100.  The PS6100 is RAID10 and in its own storage pool, the PS4000 is RAID6 and in its own storage pool.  The PS6100 has a single 5.5 TB thin provisioned volume (total available is 5.75TB), the reconfigured PS4000 has a single 4 TB thin volume (total available is 5.66 TB).  About halfway through storage vmotioning the VMs from PS4000 to PS6100, SANHQ began reporting 4.2 in-use space warnings on the PS61000 volume even though in Group Manager the reported in-use space for the volume and pool was only around 2 TB with the rest marked free.  Once the PS4000 was reconfigured and its volume created and about 1.1 TB migrated back, that volume began throwing 4.2 errors as well.   SanHQ reports 4.2 errors, both volumes currently as over 99% full, even though Group Manager shows the volumes as much less full -- the PS6100 is at about 70% full, the PS4000 only 30% full (volume, pool is only 20% full).  My understanding of thin volumes with VMware is that they only grow represented by how much space has been consumed by the upstream filesystem (eg, VMware VMFS) and only "shrink" if you manually unmap them (VMware) or run some other operating system that automatically does unmap.  That being the case, none of my thin EQL LUNs have ever shown more than 70% space utilization (maximum) and some never more than 25% maximum, yet San HQ is throwing 4.2 errors.   Why? 
SAN HQ Alert 4.2 in-use space on volume