How to Choose a Bioactive Clean-Up Crew – Reptilinks

Many reptile owners choose bioactive as their enclosure type—meaning an enclosure comprising living elements, such as plants, bugs, and microbes that work harmoniously. Contrary to popular belief, bioactive enclosures are possible regardless of what kind of humidity or temperature your animal naturally lives in. After all, reptiles originally come from the wild! Mimicking nature in captivity is possible in a wide range of situations.

However, replicating the natural world through bioactive enclosures means making some important decisions—including which types of organic life will survive in the bioactive environment. Here are some tips for choosing the right clean-up crew for your bioactive enclosure so you don’t spend money on bugs that won’t live long.

The Most Common Types of Clean-Up Crew

The clean-up crew (often abbreviated as CUC) in a bioactive enclosure serves many purposes. It cleans up natural debris, such as reptile feces and decaying plant matter. It also stirs the substrate, aerating it and providing water access for plant roots. Just like in nature, the bugs, mites, and other small creatures that litter the ground play an essential role in the ecosystem.

Regardless of what kind of environment your reptile or amphibian lives in, they will need some small bugs or microbes as part of their bioactive setup. It is a common misconception that only humid enclosures can use bioactive!

In general, there are three main types of CUC that should be included in a bioactive terrarium.

The Insects

Insects are sort of the top of the CUC “food chain”—they’re usually the biggest, and they break down the largest portions of debris, producing waste themselves that smaller participants in the cycle consume or otherwise use. Isopods (which look like pill bugs) are the most common type of insect used in a clean-up crew, but they are far from the only possibility. Beetles, roaches, and even millipedes can all play a role in a naturalistic terrarium environment by consuming plant matter, feces, and fungus.

The Detritivores

The term “detritivore” comes from the word “detritus” and “-vore,” or “to eat.” In other words, detritivores eat leftover organic material—usually dead plants. The detritivores in a bioactive enclosure will keep plants healthy and prevent the buildup of imbalanced acidic or gaseous substrate that can happen when plants rot on the floor without cleanup.

Usually, springtails are the detritivore of choice for bioactive enclosures. However, they need moisture to thrive, so more arid bioactives will need to explore other options. We’ll get to that in a bit!

The Decomposers

Decomposers are similar to detritivores, but their diet consists more of dead organisms and organic waste material, like feces. In most soil-based enclosures, earthworms are a common option as a decomposer, but not all bioactives rely on dirt.

Understanding CUC by Biome

To choose the right clean-up crew for your bioactive terrarium, you will need to consider two main things: food sources and moisture. Many types of CUC can only live if the moisture content is high enough for them to molt; otherwise, they become too dry and end up trapped in their shedding shells, which constrains them until they die.

Food sources will also be dictated by moisture, as certain plants will only grow in specific moisture levels, too. Thus, we can break bioactives down into three rough categories for the purposes of a clean-up crew:

Desert

Desert bioactives can be some of the toughest to break into when it comes to the CUC because the most common options, like widely available springtails, will not thrive here. For insects, powder orange and dwarf white isopods can enjoy the dry climate, though they will need some protected areas (such as underneath cork bark) that remain slightly more humid than ambient. Dermestid beetles and even dubia roaches are other alternatives.

Despite the dry air, arid springtails are available—they’re just not usually what you can find in a store that stocks springtails. Remember that all animals need a bit of moisture, so if your springtails are dying off, remember to keep the underlying layer of your desert enclosure somewhat moist so they can burrow.

As for decomposers, in desert environments, many insects play a double role here. Earthworms don’t have enough moisture to survive, so trust your dermestid beetles to clean up dead bug waste and discarded shells. Even mealworms can help!

Semi-Arid

Semi-arid enclosures represent the general spectrum of most reptile keeping: a bit moist, but not saturated or in need of regular misting. Insects such as zebra isopods are highly resilient in these environments, and as with most enclosures, small roaches such as discoids will thrive. Semi-arid terrariums are the purview of many new reptile keepers who are experimenting with common species such as leopard geckos; if you have a soft-skinned reptile or amphibian such as this, consider avoiding dairy cow isopods, as they are known to be hungry enough for protein that they may nibble on your animal, too.

Springtails can survive in semi-arid enclosures if they have exposure to a small humid area; whether you will need arid springtails or the more common Folsomia candida depends on whether your enclosure tends toward the dry side or the damp side.

For similar reasons, earthworms may or may not be viable in this middle range. If not, defaulting back to dermestid beetles, millipedes, and mycorrhizae (a fungus that hangs out around plant roots) can be a great alternative.

Humid

Humid enclosures are where the greatest number of options typically lie for CUC. Diary cow and many other varieties of isopods thrive here, burgeoning in number as long as they have a safe place to hide and plant matter to eat. Dubia roaches also do extremely well, as the humidity ensures proper molting.

Detritivores include Folsomia candida, which will find their way to pooled water or moist soil and can often be seen by the naked eye springing around. Earthworms will contribute in the damp soil and are a great option for this type of enclosure. Depending on enclosure size, nightcrawlers may also be appropriate.

Consider adding mites as well, as humid enclosures tend to struggle with fruit fly and gnat problems. Hypoaspis miles is a frequent choice, as these small contributors eat pest eggs (however, they can also eat your springtails! It’s all about balance).

When CUC Are Food

One thing new bioactive users often forget to account for is the fact that many CUC are bugs—and lots of lizards love bugs. It’s common to wonder where your CUC went only to realize that your lizard or frog isn’t hungry anymore because they’ve been snacking.

As long as the enclosure is maintaining a healthy ecosystem, this is completely fine (although it can be cumbersome if you need to keep replacing your CUC!). Dubia roaches and earthworms are the most common victims, as many reptiles find isopods less tasty due to their hardness. If your CUC has plenty of plant matter to eat, they are already gutloaded. However, if something in the enclosure is providing a regular protein source for the bugs, animals that eat your CUC could be susceptible to gout.

If providing a constant smorgasbord of snacks is not what you had envisioned for your pet, there are ways to discourage the behavior. Choose clean-up crew that are too large to ingest (or too small to notice)—swap earthworms for nightcrawlers and so on. Provide the CUC with plenty of places to hide so that they can escape the predator they share a space with. And if you’re still having trouble, consider changing the décor to alter the lighting within the enclosure. Most CUC like it dark, and you can change their movement patterns (away from your animal) by changing the areas exposed to illumination.