Tank transfer advice.

[Ann Enomy]

I have an 120 gallon reef tank in my office waiting room and will be getting a 220 gallon tank. I have the luxury of space so my plan is to set up the new tank on a different wall. I have back up return pumps and heaters and can get basic circulation going on the new tank while keeping the old fully functional. Few questions:
1. Is a full new tank cycle needed or preferred? everything except substrate is eventually going into the new.
2. if no, should I just transfer everything in one day?
3. Should I use "old" water from water changes to fill new tank tank to ensure parameters are the same between tanks
4. Any advice from those who have lived through this. I'm planning on it being a whole big messy day but if anybody can offer pointers on making it go smoother i would appreciate it.
Thanks

 

[get-salty]

I did a 65 to 120gal

i replaced the sand and rocks with new ones.
threw few old rocks into the sump and let it run w/out lights for a week.
Parameters were ready and cycled within a week.

Going to be a ton of work.
Good luck and happy reefing !