Size the enclosure to the spider now
Choose the Monocentropus balfouri 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 Socotra Island Blue Baboon grows, increase enclosure size in sensible stages instead of jumping straight from a sling tub to an adult display.
Lifestyle changes the shape
Because Monocentropus balfouri is terrestrial, enclosure proportions should support that lifestyle. Floor space, height and substrate depth are not interchangeable.
The right dimensions for Socotra Island Blue Baboons are therefore about usable space, not simply litres or centimetres on a product label.
Fall distance and hard decor
For Monocentropus balfouri, 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 Socotra Island Blue Baboon enclosure and position them so normal digging cannot create a dangerous landing area.
When the enclosure is too small
Rehouse Monocentropus balfouri when the retreat no longer fits, required substrate depth is compromised or routine access to water and feeding has become awkward.
A Socotra Island Blue Baboon 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 Monocentropus balfouri enclosure completely before the move. Add substrate, retreat and water, then check ventilation and security.
Moving a Socotra Island Blue Baboon into a finished enclosure keeps the transfer short and avoids trying to adjust decor while the spider is exposed.