I found this old aquarium heater and was wondering if it work for ants? I'm not sure if water conducts heat differently, or if it could have different results outside water. It is a 15-watt flat aquarium heater meant for 4 gallon(15.1416 liter) aquariums. The dimensions are 5.715cm by 16.51cm by 0.4064cm.
Heres pictures for more info: https://imgur.com/a/lQSpwgu
If you think it would work could you also tell me how I should position it for test tubes? I have no clue XD
All help is appreciated!