How to transition to new tank?

I Currently have a 70g tank with 2 clowns, 2 blue/green chromis, 1 chalk bass, one torch frag, two zoa frags. I have about 80lbs rock and sand that I plan on replacing. The new tank is a 120g. I still have a bit of work to do on the stand but it shouldn't take too long. What I want to know is can I keep my fish and coral in a 20g tank for a week or two while I get everything ready? I have already sold the 70g tank and stand to a friend so I really want to get it to him.