Gestroi Isopod — Fact Sheet

Armadillidium gestroi · Gestroi Isopod

📋 At a glance

🏠 Enclosure

• Housing: Indoor, cross-ventilated colony tub with fine side openings for mancae.
• Starter size: At least 25 × 18 × 15 cm for 10–20 animals; add floor area and feeding points as numbers rise.
• Substrate: 6–8 cm of deciduous leaf mould, decomposed hardwood and pesticide-free mineral soil.
• Gradient: About one-third damp, a lightly moist middle and a less-wet ventilated end; retain slight deep moisture.
• Avoid: Uniformly soaked or fully dry substrate, coir-only mixes, fertilizers, pesticides and aromatic wood.

🪨 Enclosure furniture

• Thick pesticide-free hardwood leaf litter.
• Soft rotten wood and cork flats with air spaces beneath them.
• A moss station at the damp end.
• Cuttlebone, limestone or clean calcium carbonate available continuously.
• Stabilize heavy pieces so burrowing animals cannot be crushed.

💡 Lighting

• UVB: Not required; no specialist lamp or replacement schedule is needed.
• Cycle: 10–14 hours of diffuse room or plant light, optionally shorter in winter.
• Provide deep shade beneath leaves and cork.
• Avoid direct sunlight and hot spotlights.

🌡️ Temperature

• Warm-side upper target: 22–25 °C

• Ambient zone: 18–25 °C

• Cool retreat: 16–20 °C

• Night: 16–22 °C

• Avoid sustained temperatures above 27 °C; forced dormancy is unnecessary.

• Check probes within the litter at both ends.

• If heating is unavoidable, thermostat one outer wall and keep the moist refuge opposite; never heat the whole base.

💧 Humidity & water

• Working range: 55–75%; keep the molt refuge at 65–80%.
• Pour water into the moss end as needed; never soak the whole surface.
• No open water dish or soaking is required.
• Repeated clustering in moss or incomplete molts suggests dryness; condensation, sour odor or animals high on cork suggests waterlogging and poor airflow.

🥬 Diet

Feed freely:

• Decomposing deciduous leaves and soft white-rotted wood.

In moderation:

• Carrot, squash, sweet potato, mushroom, courgette or balanced isopod food 2–3 times weekly.
• Modest dried shrimp, gammarus or quality fish food about once weekly.

Avoid:

• Seasoned scraps, conifer litter, pesticide-contaminated garden material and oversized protein portions.
• Wet leftovers older than 24–48 hours.

Supplements:

• Permanent cuttlebone, limestone or clean calcium carbonate.

🩺 Health warning signs

• Incomplete molts or post-molt deaths → dry refuge, unstable humidity or inadequate calcium.
• Colony remaining only at the moss station → the rest of the substrate has dried too far.
• Constant climbing, condensation or sour smell → waterlogging and insufficient ventilation.
• Mites or mold around food → oversized portions or delayed removal.
• Rapid colony decline in a warm bioactive enclosure → excessive temperature, predation or chemical exposure.

For persistent unexplained decline, isolate the colony and consult an exotics veterinarian or experienced terrestrial-isopod specialist.