Sand seeding/transfering sand between tanks

[Riptide]

I have a 90 gal with 40 gal sump with about 20-30lbs of sand in it, the sand has been in there for about 2-3 weeks, tank and rock has been going for about a month or so. I have a 10 gal tank with about 10 - 15 lbs of well seeded sand. I want to add another 40 lbs of sand on top of what I have in my 90 gal and then take the 15lbs out of my 10 gal tank and spread that on top, does anybody see any problems with me doing that. I also have a torch, hairy mushroom, various mushrooms and some green star polyps in the 90 gal

I know doing something like that to well seeded sand would probably kill off most everything hat I wold want o keep...but laying well seeded sand overtop shouldn't be a problem should it? Just wondering about releasing amonia or something stupid like that. any help is appreaciated...thanks Joe