I already read that 100% is not recommended unless absolutely necessary. Here is my setup. I have rocky substrate with sand and small gravel mixed with it. As I moved the rocks around, the small stuff all went to the bottom and top layer is rocks only. It is hard to plant plants on rocks. I want to take out the whole substrate and rearrange them and put more gravel on top. I have guppies, some live plants, mystery snails and pond snails/trumpet snails. My cycle is complete and I have a HOB filter. I was thinking of moving the fish to a bucket with the filter media, take out all the substrate to another bucket to keep bacteria alive, cleaning the tank with running water, lightly rinsing the substrate and putting everything back together. Is this the best way? Please advise.