These cables are great for heating your ants, whether they are in a full size formicarium or in a test tube. Heat cables help the eggs, larvae, and pupae grow faster and keeps the ants happy. Place the heat cable on top of the nest or at the exit part of the test tube. This will create a gradient of heat and the workers will move the brood to the best location based on their ideal temperature.
Note: Only about half of the cable heats up. This is normal.