Size the enclosure to the spider now
Choose the Cyriocosmus elegans enclosure for the spider's current size, not the maximum adult measurement. The spider should be able to find prey, water and its retreat without being lost in unused space.
As a Trinidad Dwarf Tarantula grows, increase enclosure size in sensible stages instead of jumping straight from a sling tub to an adult display.
Lifestyle changes the shape
Because Cyriocosmus elegans is fossorial, enclosure proportions should support that lifestyle. Floor space, height and substrate depth are not interchangeable.
The right dimensions for Trinidad Dwarf Tarantulas are therefore about usable space, not simply litres or centimetres on a product label.
Fall distance and hard decor
For Cyriocosmus elegans, keep fall risk in mind when deciding how much open height sits above the substrate. Heavy-bodied terrestrial spiders especially should not have a long drop onto hard decor.
Keep stones and heavy cork secure in the Trinidad Dwarf Tarantula enclosure and position them so normal digging cannot create a dangerous landing area.
When the enclosure is too small
Rehouse Cyriocosmus elegans when the retreat no longer fits, required substrate depth is compromised or routine access to water and feeding has become awkward.
A Trinidad Dwarf Tarantula touching a wall is not, by itself, proof that the enclosure is too small. Look at how the whole setup functions.
Prepare the next size first
Set up the new Cyriocosmus elegans enclosure completely before the move. Add substrate, retreat and water, then check ventilation and security.
Moving a Trinidad Dwarf Tarantula into a finished enclosure keeps the transfer short and avoids trying to adjust decor while the spider is exposed.