Orchids have the undeserved reputation of being difficult to grow, when in fact they are no more temperamental than any other plant as long as you meet their basic requirements. While they prefer a humid environment, they cannot tolerate soggy soil. Orchids don't like variances in temperatures such as a cold breeze from a window or the blast from central heating. A mini greenhouse is an ideal location for them.
Short Orchid Plants
Prepare the charcoal. Wash the charcoal to remove any dust by running water over it for a few minutes. Let drain on paper towels to remove excess water. Blot dry.
Lay a 2-inch-thick layer of charcoal on the bottom of the aquarium.
Place the orchids on the charcoal still in their pots. Orchid pots have slots for drainage. Most orchids grow in a bark medium and not potting soil since potting soil retains too much water. Fill in between and around the pots with the orchid growing medium.
Replace the lights in the aquarium lid with grow lights.
Tall Orchid Plants
Cut the plexiglass panels slightly smaller than the dimensions of the sides of the aquarium, but taller. For example, if the aquarium is 20 inches wide on two sides and 15 inches on the remaining sides, cut the panels to 19 15/16 inches and 14 15/16 inches wide and about 6 inches taller than the tallest orchid plant.
Place the panels inside the aquarium. With three of the panels, tape the outside of the panel to the outside of the aquarium at the edge where the aquarium ends. If you wish, tape the sides of the panels together as well. This will stabilize the panels. The fourth untaped panel is easily removable to access the plants and interior of the mini greenhouse.
Locate the mini greenhouse by a window where it will receive indirect bright light.