Formicarium

A formicarium (plural formicaria) is any artificial home built to keep ants. You'll also hear it called an ant farm. In most cases it has two parts: the nest, a dark and humid area where the queen lives and the brood is raised, and the outworld, an open area where the workers find food and water.

There are many kinds of formicaria. Test tube setups are the simplest. Then there are Ytong nests made of aerated concrete, acrylic nests built from layers of clear plastic, sandwich nests filled with sand or soil, wooden nests for wood-dwelling species, and naturalistic setups that try to copy the ants' natural habitat as closely as possible. Some products, like all-in-one glass or acrylic kits, combine nest and outworld in a single piece.

The right formicarium depends mostly on your species. Messor barbarus needs a mix of humid brood chambers and dry seed chambers, Crematogaster scutellaris feels at home in wood, and tiny escape artists like Pheidole pallidula need a setup without any gaps.

In practice

• Pick the formicarium for your species, not just for its looks: humidity, size and how easily the ants chew or escape all matter.
• Make sure the nest has a way to stay humid, like a water tank, a hydration chamber or a test tube.
• Size it to the colony. A huge formicarium stresses a small colony, so upgrade step by step.
• Choose a setup you can clean and feed easily, because you'll be doing it every week.