wont the dirt get kicked up every time you trim or replant?
Yes, but not too badly. It'll settle back kind of like in a lake. Luckily, this topsoil luckily settles really quickly. I'd just have to turn the filter off until it was clear enough. I am also doing a dry start method on this tank.
It'll get cloudy any time a fish gets near the bottom as well. Just be ready to do a lot of filter cleaning, this and fine particulate settling on plant leaves are my biggest gripes with soil tanks, and I've always done them with caps.
I am planning on dry start method to fix that problem. I will not have bottom feeder fish, only angelfish, otocinclus, and maybe some wild type shrimp in there. The particulate wont really get on the dwarf hairgrass I think, and if I have shrimp then it will be cleaned off by their activity.