Hi, and welcome to AA!
Congrats on your new tank. Those bowfront tanks are really beautiful. I agree about just moving the old filter over with the fish. I've started many tanks this way with excellent results every time. Just keep an eye on perams for a few days and be prepared to change some water, but you may not even have to do that. I'm not sure I know what you mean by marine sand, like crushed coral? That could raise your pH, which may be problematic for your fish, since the species you have prefer softer water with a lower pH, like 6.5-7.0. If you want marine sand because you like the look of white sand, I would suggest pool filter sand. You can get a 50 lb. bag for about $10 and it is heavy enough to stay out of your filter, plus it won't alter your water chemistry.