tank upgrade Q's

[burrows14]

Im gonna be upgrading systems in the next few weeks from a 4ft 120g to a 5ft 120 gal and kind of wanting a fresh start. I plan on moving my rock corals equpment and fish over but I want to use new sand and new water as I have had a couple battles with ich and cyano. I know I will be transporting some of the cyano in with my rock but will the tank go thru a cycle? I would be doing the change over an afternoon removing the old and replacing it with the other. Any input would be great!

Cheers
Ray