I took a deposit before 1 April 2013 and the tenancy has since renewed. Do I need to protect?
If you entered into a new fixed term agreement with your tenants after 1 April 2013, yes. As a new agreement it is considered a new deposit. It must be protected within 14 days of the agreement being entered in to.
If the tenancy continued on a statutory periodic basis it does not need to be protected.