Just got a new 125 l tank, and am so excited. i have upgraded tanks before and also kept live plants with varying success rates! I could do with some advice please, as I really would like to get this tank nicely planted. Was plaaning to use play sand as the substrate as I prefer the look as opposed to gravel. Should I do anything to the sand first in order for plants to thrive? Should I add a thin layer of soil underneath? If so is it regular soil from the garden or should it be something more exotic!!!!!