A bioactive terrarium (or

vivarium A vivarium (Latin, literally for "place of life"; plural: ''vivaria'' or ''vivariums'') is an area, usually enclosed, for keeping and raising animals or plants for observation or research. Water-based vivaria may have open tops providing they a ...

) is a terrarium for housing one or more terrestrial animal species that includes live plants and populations of small

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s and

microorganism A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

s to consume and break down the waste products of the primary species. In a functional bioactive terrarium, the waste products will be broken down by these

detritivores Detritivores (also known as detrivores, detritophages, detritus feeders, or detritus eaters) are heterotrophs that obtain nutrients by consuming detritus (decomposing plant and animal parts as well as feces). There are many kinds of invertebrates, ...

, reducing or eliminating the need for cage cleaning. Bioactive vivariums are used by zoos and hobbyists to house reptiles and amphibians in an aesthetically pleasing and enriched environment.

Enclosure

Any terrarium can be made bioactive by addition of the appropriate substrate, plants, and detritivores. Bioactive enclosures are often maintained as display terraria constructed of PVC, wood, glass and/or acrylic. Bioactive enclosures in laboratory "rack" style caging are uncommon.

Cleanup crew

Waste products of the primary species are consumed by a variety of detritivores, referred to as the "cleanup crew" by hobbyists. These can include

woodlice A woodlouse (plural woodlice) is an isopod crustacean from the polyphyleticThe current consensus is that Oniscidea is actually triphyletic suborder Oniscidea within the order Isopoda. They get their name from often being found in old wood. ...

springtail Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects (the other two are the Protura and Diplura). Although the three orders are sometimes grouped together in a class called Ento ...

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

millipede Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a resu ...

s, and various

beetle Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

s, with different species being preferred in different habitats - the cleanup crew for a

tropical rainforest Tropical rainforests are rainforests that occur in areas of tropical rainforest climate in which there is no dry season – all months have an average precipitation of at least 60 mm – and may also be referred to as ''lowland equatori ...

bioactive terrarium may rely primarily on springtails,

isopod Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, an ...

s, and earthworms, while a desert habitat might use beetles. If the primary species is

insectivorous A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores were ...

, they may consume the cleanup crew, and thus the cleanup crew must have sufficient retreats to avoid being completely depopulated. Additionally, bioactive terraria typically have a flourishing population of bacteria and other

microorganisms A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

which break down the wastes of the cleanup crew and primary species.

Fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

may occur as part of the terrarium cycle and will be consumed by the cleanup crew.

Substrate

Bioactive enclosures require some form of substrate to grow plants and to provide habitat for the cleanup crew. The choice of substrate is typically determined by the habitat of the primary species (e.g. jungle vs desert), and created by mixing a variety of components such as organic topsoil (free of pesticides and non-biological fertilizers), peat, coco fiber, sand, long-fiber sphagnum moss, cypress mulch, and orchid bark in varying proportions. In wet habitats, there is typically a drainage layer beneath the substrate to allow water to pool without saturating the substrate. The drainage layer may be constructed via coarse gravel, stones, expanded clay aggregate, or may be wholly synthetic; the drainage layer is typically separated from the overlying substrate with a fine plastic mesh. Additionally, some bioactive terraria include leaf-litter, which can serve as food and microhabitat for the cleanup crew.

Plants

The use of live plants in a bioactive terrarium provides cover for animals inhabiting the enclosure, is aesthetically pleasing in a display enclosure, and can help to absorb nitrogenous wastes that could otherwise build up in a system. Providing a variety of plants that will grow in and be clipped back during maintenance provides hiding spots for terrarium inhabitants that change over time. This is a form of enrichment recommended for keeping reptiles.{{Cite web, url=https://www.aazk.org/wp-content/uploads/Suggested-Guidelines-for-Reptile-Enrichment.pdf, title=Suggested Guidelines for Reptile Enrichment, last=, first=, date=, website=American Association of Zookeepers, url-status=live, archive-url=https://web.archive.org/web/20211113060515/https://www.aazk.org/wp-content/uploads/Suggested-Guidelines-for-Reptile-Enrichment.pdf , archive-date=2021-11-13 , access-date= Bioactive Arid Vivarium

References

Biology