Table of contents
Care guide written by Lie-Pretend
Isopods are crustaceans, not insects. They are much closer related to a crab than to an ant. There exist both terrestrial (land) and aquatic (water) isopods.
They all have segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs, and five pairs of pleopodal lungs (modified gills). Isopod comes from Greek, meaning "equal feet" because taxonomists are both pretentious and lazy.
Females carry their eggs in a "marsupium" pouch on their stomach.
The genius Armadillidae, Armadillidiidae, Eubelidae, Tylidae and some others can roll into a ball (conglobate) as a defensive mechanism, to hibernate, or conserve moisture.
Some (Gestroi, Klugii, Maculatum, etc.) exhibit Batesian Mimicry, where a harmless species evolves to imitate the warning signals of a harmful species.
This guide is for terrestrial isopods.
Isopods are migratory, and they breathe using gills.
What this means is they require high humidity to live and molt, then they migrate to a dry area to let their carapace harden, then they return to the wet. They do this little loop often and regularly.
To replicate this is relatively simple, just create a gradient across the enclosure from dry to wet. The dry side should have many ventilation holes, the wet side only needs a few.
Dry side = dry sphagnum moss, cork bark, dead leaves
Middle = dirt mixed with wood mulch, worm castings, dead leaves
Wet side = living pillow moss, living sphagnum moss, cork bark, wood
If you don't want to use living moss on the wet side, soak dry sphagnum in water to keep it damp. Living moss is preferable because it is both a food source and holds moisture.
You don't need a water bowl, or water crystals. Just mist the wet side once a week or when you don't see condensation. Isopods are clumsy and can easily drown in small pools of water. They should get all the moisture they need from their environment.
Also, they are poor climbers, and can not get up glass or smooth plastic walls.
I'm going to break this down a little bit, because each has varying needs of the same general foods.
Always = dead leaves, damp wood, moss, calcium (Baked eggshells, cuttlebone, limestone)
Sometimes = dried shrimp, fish food**, raw root vegetables, rice is nice
Never = raw/cooked meat, table scraps, oils, salts
** Some fish foods contain copper sulfate, which is necessary in small amounts, but can be harmful in large doses. Use higher quality fish foods or shrimp safe foods.
When feeding, it is important to make sure that you don't overfeed. Ideally most of the meal should be gone in a couple days. This is to stop mold and bacteria growth in the enclosure.
Isopods are born from a brood chamber, known as a marsupium, and emerge as juveniles, called mancae. They will molt multiple times and develop into full adults within a year. They will live as adults for 2-3 years. Making their entire life cycle approximately 4 years. This is an example of incomplete metamorphosis.
Depending on the species, you should expect at least 10-20 mancae per female per brood. You should expect 1-3 broods per year. Some species are far more prolific than others, and have significantly larger broods.
An honorable mention, because they coexist so well with isopods. Springtails eat mold, most of the detritus that isopods create, and need no extra attention beyond the care given to the pods. Just drop them in and they'll do the rest.
Sources
https://www.reddit.com/r/isopods/s/xYZADpgYeq