How does a terrarium get water...?!!?

Question

Explain the process of the water cycle in a sealed terrarium.

Answer 1

You add the water to the terrarium, and it then recycles that water.

The terrarium is kept warm due to the Greenhouse Effect. Sunlight enters the terrarium along with heat waves. The sunlight can escape the terrarium, so you can see what is inside, but most of the heat is retained. This then drives the water cycle of evaporation and at night condensation. So the plants can breath in and out the water that is in the terrarium. The cycle isn't perfect so you need to add a little water each month, but it is a very efficient way to recycle the water. The heat in the terrarium drives the water cycle which is evaporated during the day and forms condensation at night so the plants can suck it up. A plant actually breathes in carbon dioxide and breaths out oxygen. When it does this it also loses water. This is why cactus have thorns instead of leaves they lose less water. In the terrarium the water that escapes the plants can’t easily escape the terrarium so it re-enters the water cycle.

The same thing happens on the Earth. Water is evaporated by heat; it combines with dust to from clouds and rains out. Or it appears as condensation on the surface of the Earth at dawn; we call it dew. When the water hits the Earth it runs downhill and eventually reaches a river or stream that empties into the ocean. Or it sinks into the ground and joins the underground water supply. This can happen in a terrarium if the water sinks down through the soil and reaches the bottom of the terrarium. This is why it is best to put a gravel base in your terrarium. The roots of the planets can absorb that water from there as well as absorb the water that forms on them through condensation.

One good thing to do if you get an insect infestation inside your terrarium is to have a smoker blow a couple of puffs of tobacco smoke inside. Nicotine is a major ingredient in many pesticides so it can do the same job in your terrarium (Hopefully this will remind people that smoking is the inhaling of poison.)