adding dirt to an established tank?

The method mentioned here sounds pretty cool and somewhat easy. But, if you have to move the sand back in order to bury each piece of frozen dirt, you would be moving your stemmed plants anyway. So you really would be required to move things around as you are going through the process for each piece.
Why not just remove everything and start from the bottom up? Get a large plastic tote, one like we all probably use to store things in, and remove tank water to fill it up, move your filter to this location and move the tank inhabitants to the tote.
I just did this to my 46 gallon 2 days ago. Yes, It took me 7 hours to complete, but I felt like working from the bottom up was the easiest way to get the job done. Besides, don't you have dolomite and muriate of potash to lay under the soil? Since you are planning to rescape this tank anyway, I suggest what I mentioned about the tote. I also took each plant species and used a plastic storage container to separate them so that would be easier when re planting. Use the sand on top of the dirt, you get to keep most if not all of your BB in the substrate, the filter stays running so you do not lose any there and you are free to take your time. It was easiest for me to get my fish out once I had removed the plants and about half of the water. The only part that was difficult was that I had to find a place to put the sand until I needed it again. I ended up using a cooler, only because it was all I had left to use.

This suggestion is merely based on my own experience and I am in no way saying that it is the only method. Just what worked for me. :)
 
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