Adding additonal substrate should not cause the old to recycle. Put the old substrate on top of the new. IMO
you might want to look at a DSB
before you do this move. If you ever had thought about doing on in the past now is the time to do it on the move.
Do you have live rock?
This is how I would do it. (assuming you continue with the aragonite).
Mix up plenty of new saltwater and let age 1 day at tank temp.
Put the new substrate on the bottom of the new tank. Put corals and fish in 5 gal
buckets for temporary storage. Fill buckets 3/4 full with tank water from old tank.
drain out most of the old water into a 30 gal
trashcan off to the side.
Scoop and trasnfer old substrate to new tank.
Put bowl in new tank and pump in old tank water from trashcan.
Pump in new freshly mixed and aged saltwater till 3/4 full.
Put in fish and corals from buckets.
top off tank with new water and start up your pumps.
CLean old tank and put away.