In my coming Tomato Frof Vivarium, for misting/watering of the plants, I hooked up a small 2" round mist sprinkler head to a 12V 1/8" line water pump, and it works great, leave it on for 5 seconds to lightly mist their vivarium, and leave it on for 15 seconds to simulate rain, then pump the water back out of the false bottom once it's drained through the substrate.

~Royce