My thought would be minimal fragging if possible. When you start over it would seem a lot more awesome to have colonies vs small frags. One good thing about fragging is that you can have multiples so if something bites the dust you have a back up. Also, some of the colonies would take on new and different characteristics with differing placements - I had a red planet that was accidentally fragged that looked completely different because I had them in defferent spots in the tank.
I am thinking of going ready made on the new footprint - it is a pretty common size so it is stocked by a few places. As a bonus when Ace and I did my stand for the 90 I added in extra space for the plumbing behind the tank and the new tank will be drilled on the bottom- so, with the new tank I will not have to build or buy a new stand and canopy.
John
"Critics are men who watch a battle from a high place and then come down and shoot the survivors." Ernest Hemingway