What are isopods?
Isopods are small land crustaceans (relatives of crabs and shrimp) that live in soil and leaf litter. In a bioactive terrarium or vivarium they form part of the "cleanup crew" — the organisms that break down waste so the enclosure stays healthy without constant cleaning. Alongside springtails, they're the workhorses of a self-sustaining setup.
Why keep isopods in a bioactive setup?
- Waste breakdown: they eat animal droppings, shed skin, uneaten food and decaying plants.
- Soil aeration: burrowing keeps the substrate loose and prevents compaction.
- Nutrient cycling: their droppings (frass) fertilise live plants.
- Mould control: they graze fungal growth before it takes over.
- Live food: a calcium-rich snack for many reptiles and amphibians.
Ideal conditions
Most popular terrarium isopods thrive in warm, humid conditions:
- Temperature: roughly 21–26°C.
- Humidity: keep one side of the enclosure moist and the other drier so they can self-regulate.
- Substrate: a bioactive mix with plenty of leaf litter and some decaying wood.
- Hides: cork bark, leaf litter and moss give them cover and breeding sites.
Feeding
In an established, planted enclosure isopods largely feed themselves on natural detritus. Supplement with:
- Leaf litter (oak, magnolia, sea almond) — their staple.
- Decaying hardwood and rotting bark.
- Occasional vegetable scraps (cucumber, pumpkin, carrot).
- A protein source now and then (fish flake, dried shrimp) to boost breeding.
- Calcium — cuttlebone or crushed eggshell is important for healthy moulting.
How to start a colony
Add your isopods to a humid, planted enclosure with leaf litter and a hide. Keep one side moist, avoid disturbing them for the first few weeks, and let the population build. A starter culture of around 20 will grow into a self-sustaining colony over a couple of months in the right conditions.
Common questions
Will isopods harm my reptile or amphibian?
No — terrarium isopods are harmless and are a natural food source. Very large colonies in a sparse enclosure may nibble a weak or freshly shed animal, so keep them well fed.
Will they eat my live plants?
They strongly prefer decaying matter. Healthy, established plants are rarely touched.
Do isopods and springtails work together?
Yes — they're the classic pairing. Springtails handle mould and the finest detritus; isopods tackle larger waste. Together they form a complete cleanup crew.
How long do isopods live?
Individuals can live one to three years, and a colony sustains itself indefinitely once breeding.
Troubleshooting
- Population crashing? Usually too dry, too cold, or not enough food or calcium. Raise humidity on one side and add leaf litter and cuttlebone.
- Isopods climbing the glass? Often a sign the substrate is too wet — add a drier zone.
- Mites appearing? Grain mites are common in over-moist, over-fed cultures; reduce feeding and improve airflow.
Ready to start your cleanup crew? Browse our isopod culture and springtail culture.