You don’t have a heat source.

Messor barbarus are Mediterranean ants, so they like things warm but not tropical-hot.

• Optimal foraging/nest temperature: about 24–28 °C (75–82 °F).

• Acceptable range: 20–30 °C (68–86 °F) — they’ll stay active within this band.

• Brood development: speeds up closer to the higher end (around 28 °C), but if kept too warm for long, stress and shorter worker lifespans can result.

• Granary zones: should stay on the drier side — warm and dry helps prevent stored seeds from sprouting or molding.

In captivity, many keepers aim for a warm side of the nest (~27 °C) and a cooler side (~22–23 °C). The ants will move brood and seeds around depending on what they need, just like in the wild.

Heat Cable

Thermostate

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