Spiny Tailed Monitor (Ackie - Varanus acanthurus) Care Sheet
Ackies are the most commonly available of the Australian dwarf monitors. Care of the other dwarf monitors is similar but we will only deal with the ackie here. These active and easy to tame lizards grow to between eighteen and twenty four inches. They are simple to care for and are an excellent alternative to bearded dragons.
Housing Your Ackie
Set tank up as shown in diagram above
These sun loving reptiles come from the arid deserts of Australia. They require a high basking temperature and access to a good quality source of UV.
The best UV tube to use is a 12% desert rated lamp. Most UV tubes have a range of around nine inches. Adding a reflector greatly increases the available UV output from the tube, and can nearly double its range. UV tubes lose their effectiveness rapidly. After a year the tube will still be bright, but the UV output will have dropped to zero. In order to remain effective the tube must be replaced every six months.
Ackies need a basking temperature of 40’c – 42’c, and a cool end temperature of 20’c to 24’c. The easiest way to provide this heat is to use a spot light plugged into a thermostat. The sensor for the thermostat needs to come into the tank about one third of the way in from the cool end of the tank, and hang down to two inches above the substrate. If you want to make the tank look neater hide the cable in some conduit but make sure that the black section of the thermostat probe is exposed to the air in the tank. Set the thermostat to a background temperature of 28’c. The thermostat will allow the heater to heat the where the sensor is, to 28’c. At the cool end of the tank further from the sensor it should be 4’c – 6’c cooler, and at the basking point under the lamp the temperature should be 10’c – 15’c hotter. Leave the tank running for two hours. Check the temperatures. Always position the thermometers where the animal will sit. If the temperatures are correct leave the tank for a further two hours and recheck. If the temperatures are not correct adjust the thermostat, leave for two hours and recheck the temperatures. Keep tweaking and checking until the temperatures are correct. Always leave two hours between checking the temperatures to allow everything to settle down. When adjusting the thermostat only make small changes as even a little tweak can make a big difference to the tank temperature. If you are struggling to get the basking spot hot enough use a raised platform of logs or rocks. The higher the surface of the basking area the hotter it will be. Spiny tailed monitors require a night time temperature of 18’c to 24’c. Most modern houses will not drop below this so simply turn the heater off at night. If you have a cold house in winter then replace the white spot light with a red one and turn the thermostat down to minimum. Turn the thermostat back up to its daytime setting in the morning.
Feeding Your Spiny Tailed Monitor
Spiny tail monitors eat a varied mixture of live insects. They can be fed the very occasional pinkie or other high protein food item as a treat, but be careful as these treats are also high in fat which can cause health problems for them.
Baby monitors need insects every day. When a monitor is ready for sale it should only need to be fed insects once per day. It is best to feed the lizard in the afternoon when the animal is active and up to temperature. As the lizard needs the high basking temperatures to digest its food properly do not feed them within four hours of the lights being turned off. As the monitor matures it will need to eat less frequently. An adult monitor may only need to be fed 3 or 4 times per week.
Look after the crickets as ‘you are what you eat’. The live food will last longer if kept in a larger well aired tank like a cricket keeper, and fed spider water and cricket food.
A full spectrum vitamin and mineral supplement (such as Nutrobal) should be added to the food twice per week, and a pure calcium supplement should be added a further three times per week.
As the monitor grows and starts to eat bugs less frequently adjust the number of supplemented feeds so that the ratio remains the same. An adult lizard should be getting the full spectrum supplement once per week, and the pure calcium once or twice per week.
To dust the crickets place 8 – 10 appropriate sized insects in a large jug or clear plastic bag. Add a pinch of powder and shake to coat the insects. Feed these to the monitor. If these are all eaten and the lizard is still hunting, feed another 2 – 3 insects, keep adding more bugs until the animal is full. This extra food does not need to be dusted.
Daily Care for Your Monitor Lizard
The monitor should be offered fresh water every morning. When changing the water look around the tank and remove any mess. If you keep on top of the spot cleaning then the tank will only need to be fully cleaned about once every four weeks. When doing a full clean out put the monitor somewhere safe. Remove and clean all decoration and dishes from the tank. Remove all the old substrate and clean the tank. When the tank is dry, put in clean substrate, and replace the décor. The lizard can then return home. When cleaning the tank do not use household detergents and disinfectants as these can be toxic to reptiles. There are a range of reptile specific cleaners available.

