The enclosure needs to provide for a few basic requirements to be successful. Not only must it contain the frogs, it must also contain the fruit flies and other insects. The enclosure must also provide a small amount of passive ventilation, while at the same time retaining enough humidity to keep the frogs comfortable. Ordinary window screen does not have a tight enough mesh to keep fruit flies in. The most common material for the ventilation portion of your tank is a tight mesh screen commonly referred to as no-see-um screen. Window screen frame and premade corners can be used to build a screen frame to any custom size. You will also need a spline tool to press the screen material into the frame. The ventilation size will be dependent on the size of your vivarium, but is typically less than 25% of the lid.
Water must not be allowed to accumulate to the point where it saturates the substrate (soil). Saturated soil will become a host for harmful bacteria and fungus and can become anaerobic which will destroy your micro fauna. The substrate must be a very coarse well draining soil, which will hold some moisture but allow water to drain thru. The most common substrate that meets these requirements is a type of soil developed at the Atlanta Botanical Gardens, referred to simply as ABG Mix. A nice layer of leaf litter on top of the substrate will provide areas for the frogs to hide and allow micro fauna to flourish. The most common two are isopods and springtails. Both act as janitors, cleaning up decaying vegetation and frog waste and breaking it down into usable nutrients for our plants.
The substrate must be separated from water than can accumulate on the bottom of our tanks. We create a drainage layer of approx 1 ½” on the bottom of the tank, common materials for the drainage layer are hydro balls, gravel, spun glass material, or an actual void of material by creating a false bottom supported by egg crate material. They all serve the same purpose, an area for water to accumulate without actually touching the soil layer. As the water accumulates it will help to stabilize the humidity in the tank, but must be drained off before so much accumulates that it will saturate the soil. On top of the drainage layer, we add a substrate barrier to prevent the soil from falling into the drainage layer. The best material for this barrier is ordinary plastic window screen, some weed block materials have too tight a weave and won’t readily allow the water to pass thru to the drainage layer. Some people drill the bottoms of their tanks for easy drainage, while others use a length of flexible rubber hose to siphon off the water from the bottom of the tank.
Backgrounds are not a necessary feature, but if created correctly can provide a great deal of usable space for the frogs and plants. Cork bark is a common material for backgrounds, as is creating an artificial background with spray foam, silicone and some organic material such as cocofiber or peat moss. We create our backgrounds with a special mix of clay. Warm water is added to the dry clay mix to form a texture similar to playdough. Organics can be mixed into this clay or pressed onto the surface for a nicer appearance than bare clay. Plants and moss will root into the clay nicely. It is easiest to create your background as your first step. You can lay the tank down on the side that will be the background, press the clay into shape before standing upright and adding the drainage and soil layers. This is also the time to add ledges and small pieces of wood to the background for a pleasing visual look and to provide ledges and nooks for both the frogs and plants. The background should only extend down the back of the tank to just below the surface of the soil level, usually about 3” from the actual bottom of the tank.