A fire salamander is a heavy-bodied, ground-dwelling amphibian from cool European woodland, and its enclosure should be a slice of forest floor: long, low, damp, and shaded. For one or two adults of 6 to 8 inches, a 20 gallon long tank — roughly a 24 by 18 inch footprint or larger — is a reasonable minimum, and a small group needs a correspondingly wider floor, such as a 36-inch-long enclosure. Height beyond what fits deep substrate, hides, and a secure lid adds nothing this salamander will use.
Spending the footprint on the forest floor
What fills the floor decides whether the size works. Give the salamander several inches of moisture-holding substrate it can partly bury into, flat pieces of bark and cork laid directly on the ground as hides, and a carpet of leaf litter over open areas. A fire salamander should be able to move from its daytime burrow to its water dish and hunting ground at night without crossing bare, brightly lit ground. Two hides is a minimum — one at the damper end, one slightly drier — so the animal can choose its moisture level by moving a few body lengths, which is how it regulates itself in the wild.
Cool placement is part of sizing
Fire salamanders are unusually heat-sensitive for a pet amphibian and are healthiest kept cool, roughly in the low to mid 60s, with real stress risk as temperatures push through the low 70s for long. That requirement shapes where an enclosure of this size can live: a cool basement room or the coldest spot in the house, away from sunlit windows and heat vents — not the warm reptile corner beside bearded dragon lamps. A slightly larger enclosure in a cool room also buffers moisture and temperature better than a small one, which matters for an animal that suffers quickly when its home dries or warms. If your home cannot hold a cool room through summer, reconsider the species rather than shrinking the setup.
Water: a dish, not a pond
Despite the damp setup, a fire salamander is terrestrial and a poor candidate for a deep water section, which would steal the floor it actually needs. A heavy, shallow dish it can climb into and out of easily covers soaking and drinking. Keep the dish at one end, refresh it often, and let the substrate gradient do the rest — saturated at the dish end, merely moist at the far end. A paludarium-style build with a stream may look like woodland, but for this species it usually produces a smaller, wetter, warmer home than the salamander wants.
Signs the enclosure is failing
A salamander that spends all day soaking in its dish is often too warm or too dry elsewhere; one that never leaves a single hide may lack cover on its routes across the floor. Healthy use of a well-sized home looks like slow, deliberate night patrols, feeding away from the hide, and a choice of resting spots across the week. Also watch the lid: these are stronger pushers than they look, and a weighted or clipped, fine-mesh top is part of a finished enclosure, not an accessory.
Because the cool placement and damp routine are easy for a housemate to undo by moving the tank or over-misting, keeping those instructions in KinsLe's Family Sharing protects the setup from well-meant changes.