Not really, no. You can only actively participate in one Sharetank at a time but you are able to leave and join another Sharetank if invited without deleting your current Sharetank balance.
Please note:
- If you join another Sharetank, all members of your existing Sharetank will lose access if you are the owner.
- To regain access of your old Sharetank balance, just leave the new Sharetank you joined.