|Setting Up a Terrarium
There are many ways to set up a vivarium... hence many ways to set up a frog tank. I'm going to give you a quick run down of what is often used. I will then show you how I put together a "false bottom" vivarium. You will find what works best for you and improve on it, I'm just trying to give you a starting place.
From Left to Right
1. Gravel Bottom
The gravel bottom tank or "broken crock" (broken pieces of terra-cotta pots) is the father of all vivariums. It is the set up used in the old bottle gardens or plant terrariums. A layer of grave or pot chunks, mixed with some activated charcoal, was laid an inch or two deep and then covered with fine screen (in my diagram I show window screening but nylon stocking material works great). A thin layer of soil is put down; the screening helps keep the soil from sifting down to the gravel layer. The gravel layer allows the soil to drain and this kept the plants healthy. This is a great setup and time tested, but weighs a lot and needs to be drained occasionally. Also if you break the tank down the gravel can be hard to get rid of.
2. False Bottom
To decrease the weight of the vivarium and increase the amount of water that the tank can take without flooding the soil (important when you are trying to breed frogs and for frequent mistings), the "false bottom" vivarium was invented. Many people came up with this general idea and over time the hobby has standardized it. First, fluorescent light cover material called eggcrate is cut to the shape of the tanks bottom. Then fiberglass window screen is cut slightly larger than the egg crate. Short chunks of PVC pipe or other plastic objects are added to the bottom of the tank, forming columns, and the eggcrate and screening is added on top. A thin layer of gravel is added before the tank substrate (peat/soil) is filled in. There are many pieces to this setup, so putting it up and taking it down can be a bit slow. Also all pieces must be cleaned (bleached) before being reused.
3. Bark Bottom
A decrease in weight is great... but there are many plastic parts with the false bottom tanks and all of them need to be cleaned or replaced each time they are used to set up a new tank. A completely disposable... or maybe better called a "totally compostable" tanks might be better when you know it's only for short term use. Start with a layer of big bark chunks, then a layer of small chunks. Add a layer of bark mulch then finally the soil. This set up allows the soil to drain, but when you are done you can dump it in flower beds or compost pile and your plants will happily reclaim the nutrients from the frog waste.
Micro-habitats are often important for your frogs health. Giving them multiple environments (all of which are within their general likes) can greatly improve their life and the chance of them thriving and breeding. A visually appealing way to add some diversity to your vivarium is by setting up a waterfall or stream. Burying a powerhead or other aquarium pump in the substrate (making sure the water level is high enough and the in-flow filters is free of small rocks) with water being pumped over rocks or down a channel, can give you a stunning vivarium. It takes some practice but can easily be done. To see a little more on this topic please visit my firebelly toad pages.
5. Leaf Litter
An interesting method for doing substrate in a vivarium is to use only leaf-litter. The vivarium is initially set up without soil but instead with a thick layer of leaf-litter. Plants are left in pots or are rooted into moist leaves. As time passes more leaf-litter is added while the old litter breaks down and is compacted into a micro-fauna rich substrate.
Once you have your general setup picked for your vivarium then you need to think about what you want to cover it with. There are many possibilities but 4 main ones are used in the hobby.
1. Soil - Soil only tanks do work, but often the soil will stick to frogs, annoying them and looking bad (pearl-lite is the worst for this).
2. Moss - Many photos of frogs show them on lush green moss. Frogs (dart frogs especially) look great on moss, but it usually isn't their natural environment. Moss keeps moisture up and the softness is good for the frogs' skin. Moss often needs more light than most frog tanks receive and many mosses need a cool winter to keep growing.
3. Ground Covering Plants - Finding a plant that covers the ground, keeps growing, and looks good would be perfect ... I've never found one. If you find one, use it and please give me a start of it!
4. Leaf-litter - Leaf-litter is a great material for dart frogs (and most any frog). It often has micro-fauna that will help feed smaller frogs as well as offer plenty of places to hide. It makes the tanks look dark and so you need good lighting on it... and bright frogs. Most leaves will breakdown quite quickly in the moisture of a vivarium so you may need to be replace it regularly.
So you've seen a little of what is possible with a vivarium.
Learn more about the dart frog hobby: