Enclosure Types Overview

Choosing the right type of enclosure is one of the most important decisions you will make for any invertebrate in your care, and the range of options available can feel overwhelming when you are first getting started. Enclosures for invertebrates range from simple plastic containers that cost less than a dollar to custom-built glass vivariums with drainage layers, live plants, and automated misting systems. Each type exists because it solves a specific set of problems, and understanding what those problems are helps you pick the right housing without overspending or underdelivering on your animal's needs.

The enclosure is not just a box that holds your animal -- it is the entire world that animal lives in. It controls temperature, humidity, ventilation, light exposure, and security. It determines whether your invertebrate can burrow, climb, hide, hunt, and molt safely. A well-chosen enclosure makes daily maintenance straightforward and keeps conditions stable with minimal intervention. A poorly chosen one turns every aspect of husbandry into a fight against the container itself.

New keepers often assume that more expensive enclosures are automatically better, but that is not how invertebrate keeping works. A five-dollar deli cup with ventilation holes is the gold standard for raising tarantula slings, and no amount of money spent on a glass terrarium will make it a better choice for that application. Conversely, a tropical millipede colony will not thrive in a deli cup no matter how carefully you maintain it because the container cannot hold enough substrate or maintain the humidity gradient these animals need. The right enclosure depends entirely on the species, life stage, and your specific keeping goals.

Keepers commonly wonder whether they should invest heavily in enclosures from the start or begin with basic setups and upgrade later. The answer depends on the animal. Species that will grow significantly over time benefit from a progression of enclosure sizes matched to their development. Species that arrive at adult size and stay there can go directly into their permanent home. Understanding this distinction saves money and prevents unnecessary rehousing.

This article covers the major enclosure types used in invertebrate keeping, explains what each type does well and where it falls short, and helps you match enclosure choices to the specific animals you plan to keep. Whether you are setting up your first tarantula sling or building out a diverse collection across multiple species groups, knowing your options makes every setup decision easier.

Deli cups and small plastic containers represent the entry point for most invertebrate keepers and remain the workhorse of the hobby even for experienced collectors managing large numbers of animals. These containers are inexpensive, stackable, easy to modify with ventilation holes, and perfectly suited for small species and juveniles. A standard 32-ounce deli cup with holes melted or drilled into the sides and lid provides excellent housing for tarantula slings, small scorpions, individual mantises, and many other species during their early growth stages. The small volume makes it easy for the animal to find prey items and keeps humidity manageable with simple substrate moisture.

Acrylic and clear plastic enclosures designed specifically for invertebrates occupy the middle ground between disposable containers and glass terrariums. These purpose-built enclosures typically feature built-in ventilation, secure latching lids, and enough clarity for good observation. They come in a range of sizes suitable for juvenile through adult animals and are lighter and more durable than glass. Many keepers prefer acrylic for arboreal species because it is easy to mount vertically and drill additional ventilation holes where needed.

Glass terrariums are the most common choice for display animals and species that need larger enclosures with stable conditions. Front-opening terrariums are particularly popular because they allow access without reaching in from the top, which reduces stress on animals that associate overhead movement with predators. Glass holds humidity better than plastic and provides excellent visibility, but it is heavier, more fragile, and more expensive. Standard reptile terrariums work well for many invertebrate species with minor modifications like additional ventilation or mesh lid replacements.

Aquariums and fish tanks serve double duty for both aquatic invertebrates and species that benefit from the humidity retention of a glass enclosure with a screen or modified lid. Freshwater shrimp, crayfish, and aquatic snails obviously need proper aquariums with filtration, but keepers also repurpose small fish tanks for hermit crabs, large millipede colonies, and other terrestrial species that need stable, humid environments. The key consideration when using aquariums for terrestrial species is ventilation -- a sealed aquarium lid traps moisture but restricts airflow, which can lead to stagnant conditions and mold.

Bioactive vivariums represent the most involved enclosure type, incorporating drainage layers, live plants, isopod or springtail cleanup crews, and substrates designed to support a functioning micro-ecosystem. These setups are self-maintaining to a degree, with the cleanup crew processing waste and the plants contributing to humidity regulation and air quality. Bioactive setups work beautifully for tropical species that need consistent high humidity and benefit from the environmental complexity these enclosures provide. The tradeoff is higher initial cost, longer setup time, and the need to establish the vivarium before introducing the primary animal.

Custom-built enclosures fill gaps where commercial options fall short. Large centipede keepers often build enclosures with extra-secure lids because standard containers do not provide adequate escape prevention for strong, determined animals. Keepers housing large tarantula collections sometimes build rack systems with sliding tub enclosures for efficient space use and maintenance. The advantage of custom builds is that you can tailor dimensions, ventilation, and access to exactly what your specific situation demands.

Tarantulas use nearly every enclosure type depending on their size and lifestyle. Slings start in deli cups, juveniles move to small acrylic enclosures, and adults settle into appropriately sized glass or acrylic terrariums. Arboreal species need vertically oriented enclosures with cross-ventilation, while terrestrial and fossorial species need enclosures emphasizing floor space and substrate depth. Scorpions follow a similar pattern, though most species stay in smaller enclosures than comparably sized tarantulas because they tend to be less active and use less open space.

Mantis keeping favors tall, well-ventilated containers. Net cages, mesh cubes, and tall deli cups with mesh lids are all common choices. Ventilation is the overriding priority for mantises because stagnant air promotes mold growth that can be fatal. Many mantis keepers use containers that would seem too simple compared to elaborate tarantula setups, but the simplicity is intentional -- mantises need airflow, a surface to hang from, and enough height to molt safely, and a well-ventilated cup delivers all three.

Millipedes and centipedes share a need for secure, escape-proof enclosures with adequate substrate depth, but their temperaments create different priorities. Millipedes are calm enough that standard latching containers work fine, and their primary housing need is enough substrate volume for burrowing and foraging. Centipedes are escape artists that can squeeze through surprisingly small gaps and push lids off containers that are not properly secured. Any centipede enclosure needs to prioritize a tight-fitting, locking lid above all other features.

Hermit crabs need glass aquariums or similarly large, humidity-retaining enclosures because they require warm, humid conditions maintained across a relatively large space. The typical hermit crab setup resembles a tropical terrarium more than what most people picture when they think of invertebrate housing. Isopod colonies thrive in simple plastic bins with ventilation, and their enclosure needs are more about substrate quality and moisture retention than elaborate container design. Freshwater shrimp and crayfish require proper aquariums with established filtration, cycling, and water chemistry management that follows the same principles as fishkeeping.

The common thread across all groups is that the enclosure type needs to match the animal's specific environmental requirements. No single enclosure type works for everything, and the keeper who understands why different species need different containers will consistently provide better housing than one who tries to force all animals into the same type of setup.

Start by identifying what your animal actually needs from its enclosure before you start shopping. Write down the species, its adult size, whether it is terrestrial or arboreal or aquatic, and what humidity and temperature ranges it requires. Then look at what enclosure types meet those requirements and pick the simplest, most functional option within your budget. Resist the urge to buy the fanciest terrarium available if a basic acrylic enclosure will serve the animal just as well.

When setting up any enclosure, test it for functionality before adding the animal. Run it for twenty-four to forty-eight hours with substrate, water features, and any heating elements in place, then check temperature and humidity at multiple points inside the enclosure. This testing period reveals problems like insufficient ventilation, heat spots, or humidity that drops too quickly, all of which are much easier to fix before an animal is living inside. For bioactive setups, the establishment period should be several weeks to allow plants to root and cleanup crews to colonize the substrate.

Ventilation deserves more attention than most new keepers give it. Every enclosure needs adequate airflow to prevent stagnant conditions, but the amount and type of ventilation varies by species. Tropical species in high-humidity setups need less ventilation than arid species, but even humid enclosures need some air exchange to prevent mold and bacterial growth. Cross-ventilation -- air holes on opposite sides of the enclosure -- provides better airflow than top ventilation alone and reduces dead air pockets.

Maintain a stock of backup enclosures appropriate for the species you keep. Cracked containers, failed seals, and emergency rehousing situations happen to every keeper eventually, and having a clean, ready container available means you can move the animal immediately rather than scrambling to find or modify something on short notice. For sling keepers, a bag of clean deli cups and a soldering iron for ventilation holes is all you need. For larger species, keeping one spare of each enclosure size you use covers most emergencies.

As your collection grows, think about how your enclosure choices affect daily maintenance. Standardizing container types across similar species simplifies feeding, watering, and cleaning because you develop efficient routines for each enclosure style. Rack systems with uniform tubs are popular among keepers with large collections precisely because they make maintenance scalable in ways that a shelf full of mismatched terrariums does not.

The most frequent mistake is using enclosures with inadequate ventilation, particularly for species sensitive to stagnant air. Sealed plastic containers without ventilation holes turn into petri dishes for mold and bacteria, especially when substrate moisture is high. Mantises are especially vulnerable to poor airflow, but the problem affects all species to some degree. Drilling or melting ventilation holes takes five minutes and prevents a category of problems that kills animals. There is no reason to skip this step.

Buying enclosures based on appearance rather than function leads to setups that look great on a shelf but fail the animal living inside. Front-opening glass terrariums designed for reptiles are popular with beginners because they look professional, but many of these enclosures have screen tops that drain humidity in minutes for tropical species that need it retained. Others have gaps around doors that small invertebrates can escape through. Evaluate every enclosure for how well it meets your animal's specific environmental requirements, not how attractive it looks in a product photo.

Housing juvenile animals in adult-sized enclosures is a common shortcut that seems logical but creates real problems. A tiny tarantula sling in a ten-gallon terrarium cannot find its food, cannot maintain the humidity it needs in a small microclimate around its burrow, and sits exposed in a space far too large for it to feel secure. The progression from small container to medium enclosure to adult housing exists because it works. Each step gives the animal space appropriate to its current size while keeping environmental conditions manageable.

Neglecting escape prevention is a mistake that experienced keepers learn from quickly but beginners often underestimate. Centipedes, roaches, and many other invertebrates are remarkably good at finding and exploiting gaps in enclosure lids. A screen top held in place by friction rather than clips, a deli cup lid that does not seal tightly, or a terrarium door that sits slightly ajar is all it takes for an animal to leave its enclosure. Every enclosure should be evaluated for escape potential with the assumption that if there is a way out, the animal will eventually find it.

Failing to plan for growth and rehousing results in animals sitting in enclosures they have outgrown because the keeper does not have a suitable replacement ready. This problem compounds in collections where multiple animals are growing simultaneously and all need larger housing within a similar timeframe. Keep a mental inventory of which animals will need rehousing in the coming months and have replacement enclosures purchased or prepared before the need becomes urgent.

The right enclosure type depends on the specific species you are keeping, its life stage, and the environmental conditions it requires. There is no single best enclosure for all invertebrates, and the keeper who matches container type to animal needs will consistently provide better housing than one who defaults to the same setup for everything. Deli cups, acrylic boxes, glass terrariums, aquariums, and custom builds all have their place in the hobby, and knowing when to use each one is a core keeping skill.

Good enclosure selection directly supports good husbandry outcomes. When the enclosure is right for the animal, temperature stays stable, humidity maintains itself with minimal intervention, the animal can find food and water easily, and maintenance becomes routine rather than reactive. When the enclosure is wrong, every aspect of care becomes harder and the animal pays the price through stress, poor feeding, molt complications, or escape.

Start simple and upgrade when necessary rather than overinvesting in complex setups before you understand what your animal actually needs. A deli cup keeper who maintains perfect conditions raises healthier animals than a terrarium owner who bought an expensive enclosure but neglected ventilation or chose the wrong dimensions. The container matters less than the conditions inside it, and conditions are easier to control in setups you understand.

The investment in understanding enclosure types pays dividends across your entire keeping experience. Every new species you take on requires housing decisions, and the knowledge you build from your first setup carries forward to every subsequent one. Take the time to learn what works for your animals, pay attention to how they use their space, and do not hesitate to change the setup when something is not working. The enclosure is there to serve the animal, and adjusting it when needed is responsible keeping. Talk to other keepers about what enclosure types have worked for them with your species, because years of firsthand experience with a particular container style is worth more than any product description. The best setups in this hobby are often the simplest ones, built by people who prioritized function and then refined their approach over time.