I'm not sure if I understand this correctly!? What I understand is that you want to stop the ESXi host from using the "old" datastores", is this correct? In this case you need to detach/unmount the datastores/LUNs from the host, unpresent them from on storage system, then rescan the storage adapter on the host and - optionally - cleanup the unmounted LUNs. See e.g. http://kb.vmware.com/kb/2004605
I don't understand your question but if let say you don't want to see the old DC/cluster data store on your new DC/Cluster HOST ( you moved to new vcenter), please remove this server from storage switch zoning and old DC/cluster storage group. if you want to see all the old DC/Cluster data store in new DC/cluster, please ask your storage team to re-configure zoning and add those new DC/Cluster Hosts to existing storage group ( which was available to old DC/Cluster hosts).
Thanks Andre/dhanarajramesh for the info and link. This was the first step in my process. The second step was to remove the host from the Storage Group via the GUI for the SAN and then re-add to the secondary Storage group as dhanarajramesh suggested.