Determining the right amount of tropica soil for your aquarium

[Breezeyfans]

Considering a switch from gravel to soil in my 2.5x1 foot tank, just wondering what volume I'd need - anyone got a rough idea on litres?

[lucida]

I've got some info on Tropica soil that might help.

[Mermaidel]

I'd estimate around 3 litres, give or take, depending on how thick you want the layer to be. In my own setup, a 180-litre tank, I used 3.5 litres but only applied it to specific areas where I was planting.