I converted two tanks to it about 5 years ago. Plant growth was great but as time wore on, I found it hard to keep the nutrient levels down in the tanks eventually getting more cyanobacteria that was hard to control. It is really a place an leave option. If I was to do it again, I would put it in water permeable bags and cap it with sand. Eventually the soil structure collapses and you end up with a sensitive silt layer at the bottom of the tank, similar to what you would find on the bottom of a lake, good for the plants but not so good if you have to maintain the tank in any way.