Yeah, it's gonna suck to lose some of that biodiversity that you've spent time building up, but when you transfer tanks, you're going to stir up grud and potentially eliminate a pretty large chunk of them anyway. If I were to do it, I'd probably transfer just the sediment, and try to disturb it as little as possible, and then fill the tank and let sit for a good while before I added/did anything else. I'm kind of risk averse, so personally I would probably just cycle new sand if it were me, but if you have your heart set on it, I'd try and be as cautious as possible.