You’re probably familiar with isopods as the roly-polies you sometimes encounter wandering across the sidewalk, or the woodlice you find underneath a piece of wood or stone. However, there are many different types of isopods all over the world, living in the ocean, in fresh water, and on land. This is because they’re crustaceans, not bugs!
Isopods all look more or less alike, with armor-like multi-segmented bodies in a domed or flattened shape, hiding seven pairs of jointed limbs. Some are known for their ability to curl into a tight ball. Isopods come in a variety of colors: mostly red, orange, green, blue, purple, brown, gray, and/or white. They may be patternless or they may have a pattern of blotches or spots.
Terrestrial isopods make great low-maintenance pets, especially for people with limited space or a strict landlord. They’re also a great pet for kids, the classroom, or your office. Care is generally the same for each type of isopod, with few minor differences. With good care, estimated lifespan is 3-4 years.
Fun fact: Female isopods carry their eggs in a kangaroo-like pouch on their belly!
The size of the enclosure that you will need depends on how many isopods you want to keep. The below estimates apply to “standard”-sized isopods, not dwarf isopods.
- <30 isopods — 6qt / 1.5 gallons (11”L x 6”W x 4”H)
- 40-100 isopods — 18qt / 4.5 gallons (18”L x 12”W x 7”H)
- 100-300 isopods — 32qt / 8 gallons (21"L x 14"W x 6"H)
- 400+ isopods — 56qt / 14 gallons (23"L x 16"W x 12"H)
The enclosure can be a glass terrarium or just a clear plastic tub, depending on whether you want to display your isopods or you’re collecting them/raising colonies. However, whatever you use, it needs to be well-ventilated. If you’re using a glass terrarium, make sure it has a mesh top. If you’re using a tub, you’ll need to add a mesh panel or drill small holes in the lid and sides.
Can different types of isopods be kept together?
Although isopods of the same species tend to like to huddle together in aggregates, isopods of different species don’t get along quite so well. It’s best to only keep one species per enclosure so they don’t compete with each other for resources and extinguish each other.
However, if you want to keep isopods as part of a bioactive Clean Up Crew (CUC), it may be possible to keep a dwarf species with a “standard” terrestrial species without too much conflict.
Isopods and springtails often get along very well when kept together.
Terrestrial isopods don’t need much in the way of light — in fact, they tend to favor dimly lit areas and move away from light. Place the enclosure somewhere it’ll get indirect light. If you are keeping the isopods in a planted decorative terrarium, a plant grow light won’t bother them as long as they have things to shelter under.
Different species of isopods have slightly different temperature tolerances, but generally speaking, they’re all going to be happy between 64-78°F (with the exception of dwarf isopods, which like things above 73°F).
This temperature is generally consistent with room temperature or the lower end of the temperature gradient for a reptile/amphibian enclosure, so you probably won’t need an external source of heat for the little guys. However, if you do need some supplemental heat, stick a small under tank heater to one side of the enclosure for a boost.
Even though they’ve adapted to living on land, terrestrial isopods are still crustaceans with gills, and as such need access to moist conditions in order to stay hydrated (and alive). You want the enclosure well-ventilated enough to be able to dry out and prevent mold growth, but the substrate should still be kept moist (NOT soaked or muddy!).
Lightly mist the enclosure daily with a spray bottle to keep ambient humidity levels up. If you are using a planted terrarium, just the routine of watering your plants should be enough. However, if you are using isopods as a CUC for a semi-arid vivarium, you will need to maintain designated humid microclimates under pieces of bark, stone, etc.
Magic Potion (Armadillium vulgare) and Dairy Cow (Porcellio laevis) isopods tend to be the most resilient to lower-humidity environments.
Your isopod enclosure can be as plain or as ornate as you’d like, as long as it meets the base needs of the isopods. If you’re just breeding isopods as feeders or you collect them, there’s nothing wrong with a plain, stackable bin. However, you can also keep isopods in more ornate terrariums that you can show off as part of your home décor!
At minimum, you will need a layer of organic soil 1-2” deep. On top of that, add a thick 2-4” layer of leaf litter and/or hardwood mulch. Avoid pine bark or mulch that has been treated with dyes or other chemicals. Cardboard egg crate makes a highly functional climbing and hiding object for isopods. If you like, you can also add other décor such as animal bones, pieces of cork bark, flat stones, and live plants.
Best types of leaf litter for isopods:
- Live oak
- Sea grape
Your isopods will eventually eat all of the dead organic matter that you’ve provided for them. In addition to daily misting, expect to periodically “top up” the enclosure on leaf litter, and it’s best practice to refresh the soil by changing some of it out every 4-6 months.
Isopods are detritivores that eat mostly dead plant matter such as leaves and decaying wood, but they also help decompose vertebrate and invertebrate corpses. Also because they are detritivores, they do best on a highly variable diet — feeding them the same thing all the time is unlikely to help them thrive. So although they can survive on leaf litter and wood, it’s best to supplement their diet with other sources of nutrition. Here are some options to include:
Vegetable foods for isopods:
Protein foods for isopods:
- Fish flakes
- Freeze dried minnows
- Rejected whole prey
- Shrimp pellets/meal
- Shrimp shells
Commercial diets for isopods:
Generally speaking, if you keep up on your substrate changes and use commercial diet(s) as part of the feeding rotation, then vitamin or mineral supplementation should not be necessary. However, if you want to keep your bases covered just in case, there’s no harm in embedding a cuttlebone or egg shells into the leaf litter for calcium.
Isopods are so small that they’re generally the kind of pet that you observe rather than play with. They seem sturdily built, but they get easily injured or squished — particularly the flatter varieties.