Placing the Waterfall as you place the soil. I have selected a nice rectangular plastic container as my pool and waterfall and it is about 2 inches deep so I have to consider its placement as I put the soil in the terrarium. Put the plastic bin right on top of the spanish moss and see if the top of the bin is about level with the top of your underground den. Adjust it as necessary and put soil under it to boost it up if necessary. The add the rest of your soil so there is a nice even layer across the whole terrarium and the top of the water pool and the top of the underground den are at the same height - this is ground level now.

The Waterfall/Pool bin is in place and I am starting to add the soil The top of the pool and the top of the underground den should be about the same height. the soil will be nice and even across the whole terrarium

The Soil line in the terrarium: This picture shows the soil line. The top of the underground den and the top of the water basin are at the same height and the soil covers all the space in between. This is now the surface of your terrarium. The underground den is now actually underground and it makes it much more interesting than just looking at the soil.

Once you have placed all the soil and it all looks good lets take a look at our waterfall/pool.