Decor
- Rocks, tunnels and climbing branches at differing levels
- Damp wet box — hide with solid base and moss (shedding aid)
- Artificial foliage for a naturalistic look
- Shallow cool-side water bowl — drink without raising overall humidity much
Monitor lizards · Care guide
Dwarf Spiny Tailed Monitor Care Guide
Varanus acanthurus
The Dwarf Spiny Tailed Monitor — or Ackie Monitor — is native to Australia. Comfortably sized at around 24″, very active and great-tempered, they need dry heat, T5 12% UVB, multi-level climbing enrichment, a damp wet box, and patient handling.
At a glance
Quick facts
Key parameters for day-to-day husbandry. Full detail is in the sections below.
-
Daytime probe
86–88 °F
30–31 °C · thermostat sensor
-
Night drop
~14 °F
~8 °C · about 74 °F / 23 °C
-
Adult size
~24″
Comfortably sized monitor
-
UVB
T5 12%
Ceiling-mounted tube
01 · Housing
Enclosure & housing
Active monitors from Australia (~24″). Provide multi-level climbing branches, rocks and tunnels, a damp wet box for shedding, dry substrate, and a solid temperature gradient. Minimum size is for a single adult.
Adult minimum size
48″ W × 24″ H × 24″ D
For a single adult, or larger if you wish. Ackies are comfortably sized at about 24″. Start babies in something smaller so you can interact without chasing them around a huge viv.
Substrate
- Dry substrate — pelleted straw, dry bio mix, or coarser desert sand
- Some keepers mix sand with a dry bio mix
- Avoid fine mineral sands that can cause impaction
Cleaning
- Daily: spot clean to limit bacteria and odours
- About every six weeks: full clean if kept relatively clean — replace substrate, disinfect decor and vivarium
Housing diagram
Enclosure example
Front view 48″ wide × 24″ tall (depth 24″) · multi-level branches · rocks & tunnel · wet box · shallow water bowl
- Front proportions — 48″ wide × 24″ tall (2:1); depth 24″ — or larger
- Branches — multi-level climbing at differing heights
- Rocks — enrichment décor
- Tunnel — arched tunnel for enrichment
- Wet box — hide with solid base and damp moss for shedding
- Water bowl — shallow cool-side dish (treated water only)
- Substrate — dry pelleted straw, dry bio mix, or coarser desert sand; daily spot clean, full clean about every six weeks
Setup diagram · 1 of 2
Top-down view
Heat bulb & probe left–right positions · Recommended temps need this layout
Setup diagram · 2 of 2
Front view
Looking into the vivarium · bulb on the ceiling · probe hangs down the back
- Heat bulb — about one-quarter from one side, halfway front to back (on / through the ceiling)
- Probe — one-quarter from the opposite side, hanging down the back about halfway down
02 · Climate
Temperature & UVB
Day/night cycling, a proper gradient, and UVB are essential for metabolism, appetite, and long-term health. Humidity is managed with a wet box and shallow water bowl — not a high-humidity vivarium.
Daytime temperature gradient
When the heat bulb and thermostat sensor are placed as instructed, a probe target of 86–88 °F (30–31 °C) creates this spread. The probe point is not the basking spot.
| Zone | Temperature |
|---|---|
| Cool side | ~80 °F (~27 °C) |
| Probe point (thermostat probe target) | 86–88 °F (30–31 °C) |
| Middle | 90–95 °F (32–35 °C) |
| Warm side | 100–110 °F (38–43 °C) |
| Basking spot (hottest point under bulb) | 110–120 °F (43–49 °C) |
| Night drop | Reduce thermostat by ~14 °F (~8 °C) to approx. 74 °F (~23 °C) |
Photoperiod & night
- Winter: about 12 hours light/heat
- Summer: up to 16 hours when days are longer
- Night: reduce thermostat by ~14 °F (~8 °C) to about 74 °F (23 °C)
- Night drop lets metabolism slow — essential for rest
UVB lighting
- Recommended T5 unit with 12% UV output on the ceiling
- Mount straight across or diagonally (diagonal often places the power unit toward a rear vent)
- Replace every 12 months — UV output degrades over time
- Match UV on/off to heat schedule (morning on, evening off)
- UVA boosts appetite & activity; UVB enables vitamin D3 / calcium absorption
Humidity & wet box
Ackies are kept on dry substrate. Provide a moist wet box (hide with a solid base and moss) so they can raise humidity for themselves when shedding — reducing stuck sheds on toes and tail.
- Shallow cool-side water bowl for drinking without soaking the whole enclosure
- Always use de-chlorinated water (Reptisafe) or bottled water
Climate diagram
Lighting setup
T5 12% UVB on the ceiling (straight or diagonal) · heat dome on the warm side · match UV to heat
- T5 12% UV unit — ceiling-mounted (straight or diagonal); UVA supports appetite & activity; UVB enables vitamin D3 / calcium absorption
- Heat dome — warm side; same on/off routine as UV (morning on, evening off)
- Photoperiod — 12 hours in winter, up to 16 hours in summer
- Replace UV every 12 months — output degrades even if the tube still glows
First power-up tip
Always have the thermostat dial turned down before you plug it into the mains for the first time.
03 · Nutrition
Diet & feeding
Insect-led diet with optional plant matter. Dust every feed, gut-load insects well, and use the method of 5 while settling.
At a glance
Feeding cheat sheet
- Type
- Insects · plant matter if accepted
- Settling
- Method of 5 — feed 5 insects at a time
- Settled
- Often 10–20 crickets daily · adults may need 1–2 food-free days/week
- Dust
- Every feeding · 4:1 calcium : Nutrobal
- Water
- Shallow cool-side bowl · Reptisafe or bottled
Staple insects
Feed regularly · dust every feed
- Crickets, locusts, Dubia roaches
- Calci worms
- Vegetables if accepted (most will not eat them)
Occasional treats
In moderation only
- Wax worms, mealworms, Morios
Supplements — every feeding
Dust every feeding — live foods and salads — with a 4:1 mix of calcium : Nutrobal (4 parts calcium to 1 part Nutrobal). Mix first, then coat the food every time you feed.
Settling appetite — method of 5
New Ackies are often stressed and may not eat well for the first few days. This is perfectly normal. Until you know their habits, use the method of 5: offer five insects at a time and wait until they are eaten before adding more. That reduces leftover insects that can stress or injure the animal. Once settled, 10–20 crickets daily is relatively common; adults often need one or two food-free days each week.
Feeding style
- Hunting and chasing food provide exercise and enrichment
- Hand feeding can help bonding — excessive hand feeding can lead to obesity
Water
- Shallow cool-side bowl — for drinking without raising overall humidity too much
- Reptisafe or bottled water only — never untreated tap
Gut-load insects before offering — variety matters for calcium-to-phosphorus (Ca:P) and vitamins.
Why gut loading matters
Feeder insects must be well fed before offering. In the wild, lizards eat insects that themselves ate a wide variety of foods — providing complete nutrition and a better calcium-to-phosphorus (Ca:P) ratio.
- Use commercial gut-load foods with quality ingredients
- Add fresh reptile-safe vegetables for variety
- A single piece of carrot or potato is not enough — poor Ca:P and limited vitamins/minerals
Speak to a member of staff for more feeding advice.
04 · Behaviour
Handling & behaviour
Very active and great-tempered monitors. Settling and regular feeding come before handling.
- Step 1
Settle first
Allow the Ackie to settle and begin eating regularly before handling — we recommend at least two successful feeds first. Adapting is stressful; early handling can make it worse.
- Step 2
Short sessions
Initial sessions: 5–10 minutes only. Lengthen as the Ackie becomes more comfortable.
- Hygiene
Wash hands
Always wash or disinfect hands before and after handling to prevent bacteria transfer both ways.
- Warning
No aerosols
Do not use aerosols or plug-in air fresheners near the enclosure — the chemicals can harm your Ackie.
05 · Welfare
Health & welfare
Prevention starts with correct husbandry — heat, UVB, hydration, and supplementation working together.
Best prevention: good husbandry
Correct temperatures, supplementation, hydration, and UVB keep the immune system and gut working well — supporting essential physiological processes.
Inert substrates Paper, lino, carpet — pros & cons
Pros
- Lower impaction risk
Cons
- Limit natural behaviours such as digging
- Can increase faecal contamination (waste less absorbed)
Questions
FAQ
What size vivarium does an Ackie Monitor need?
For a single adult, a minimum of 48″ wide × 24″ tall × 24″ deep, or larger. Provide rocks, tunnels and multi-level climbing branches, artificial foliage, dry substrate (pelleted straw, dry bio mix, or coarser desert sand), a damp wet box with moss, and a shallow cool-side water bowl. Adults are comfortably sized at around 24″. Babies are easier to start in something smaller.
What temperatures does an Ackie Monitor need?
Set the thermostat probe to 86–88 °F (30–31 °C) by day with the heat bulb about one-quarter from one side and the probe one-quarter from the opposite side, hanging down the back about halfway down. That creates a gradient of about 80 °F on the cool side, 90–95 °F in the middle, around 100–110 °F on the warm side, and a basking spot of about 110–120 °F under the bulb. At night reduce the thermostat by about 14 °F to around 74 °F (23 °C).
Do Ackie Monitors need a wet box?
Yes. Add a moist area (wet box) — a hide with a solid base and moss. This gives the monitor access to higher humidity when shedding and reduces stuck sheds on toes and the tail. The main enclosure stays on dry substrate; the wet box is the humidity refuge, not a fully humid vivarium.
When can I start handling my Ackie Monitor?
Allow the monitor to settle and begin eating regularly before handling — we recommend at least two successful feeds first. Initial sessions should be 5–10 minutes only; lengthen as they become more comfortable. Always wash or disinfect hands before and after handling. Do not use aerosols or plug-in air fresheners near the enclosure.
What UVB do Ackie Monitors need?
A T5 unit with a 12% UV tube mounted on the ceiling — straight across the top or diagonally (diagonal often places the power unit toward a rear vent). Replace the tube every 12 months because UV output degrades. Match UV on/off to the heat schedule: about 12 hours in winter and up to 16 hours in summer.
What do Ackie Monitors eat?
Insects (crickets, locusts, Dubia, calci worms as staples; wax worms, mealworms and Morios in moderation) plus vegetables where accepted — most will not eat them. Dust every feed with a 4:1 calcium : Nutrobal mix. Use the “method of 5” while settling; settled animals may take 10–20 crickets daily. Adults often need one or two food-free days per week. Hunting and chasing food provide exercise and enrichment.
Next steps
Ready to set up your Ackie Monitor?
Shop heating, housing and lighting on this site, browse livestock when available, or speak to our team for a tailored kit list.
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