You can use a wall hanging fountain as a tank for a small water garden if it has a large enough reservoir and a relatively gentle flow, so that the plant’s roots and their substrate remain safely in place. This is an attractive way to bring plants indoors even in the cold winter months when there is nothing else green to look at, and many indoor plants have entered dormant phases where they do not grow or flower.
In order to set up your wall hanging fountain as a water garden, first clean it very thoroughly. Use only warm water and a brush; soap can leave unsightly deposits on your fountain, and will contaminate the water and make it difficult for your water plants to breathe. Allow it to dry and add an inch or so of aquarium gravel to the bottom of the reservoir. Then place your plant on the gravel and gently cover the roots with more gravel to anchor it in place. Good plants to use are horsetail, baby’s tears, or parrot feather. Some aquatic plants do not require gravel at all, such as sweet flag, water lettuce, and water hyacinth.
Before adding water, mount your wall hanging fountain in its final location. This will allow you to manipulate the final position of your plants without risking spills or plant loss.
Add water next, pouring it well away from the newly settled plant to avoid disturbing the root system. Use only purified water or tap water that has been filtered and kept in an open container for at least 24 hours to allow the chlorine and fluoride to evaporate. Water plants are very sensitive, and these chemicals can easily disrupt their systems.
Once the water is added, do not run your wall hanging fountain for a few days, in order to allow the plant to recover from planting shock and the roots to grip the surrounding gravel.
Water plants generally require full sunlight, so indoors they should be lit 12 hours or more daily with a fluorescent grow light. Incandescent lights produce a great deal of heat, which is undesirable for these delicate plantings. Take great care that your wall hanging fountain planter is placed well away from vents and drafts so that its temperature remains stable, and take care of your water plant as you would any other, checking the water regularly and fertilizing with special water garden pellets. You should be able to enjoy your water garden for many years.