I did a freshwater tank with a soil substrate a couple years ago. I found a bag at home depot that said it was just soil, no additives. I added in a bag of vermiculite for nutrients, a bag of course sand to prevent compacting, I think I mixed in some peat too. I used substrate heating, put the dirt down and a good layer of stone on top. As you might expect, doing anything that exposes the dirt layer to the water would cause a dirt storm.
Plant growth was amazing, however we initially got green water and massive amounts of algae because of the abundance of nutrients. A diatom filter cleaned up the water and lots of plants sucked up the nutrients. We could cut out gallons of plants each week, it was crazy.
When I moved, I hoped to move it with the substrate in place, but the movers insisted that was impossible. So I scooped it out and dumped it in an empty housing lot where it would be recycled back into the earth. I went for standard flourite and gravel for simplicity this time. I'm now obsessing in other ways now... building a 215gallon open-top aquarium with terrestrial plants behind it and suspended metal halide lighting.
Michael
Michael
