Water Gardening has enjoyed much success in recent years as the materials for building a decorative pond have become more readily available. A pond need not be large or elaborate, and many people enjoy water gardens that are nothing more than a cut barrel with water, plants, and maybe fish in it. These beautiful water gardens need not be enjoyed only during the warm months of the year, however. It is not only possible to construct an indoor water garden, but in fact there are many benefits to it over an outdoor pond. Inside the shelter of a heated dwelling, tropical fish and plants may be kept that would perish if kept outdoors in temperate zones. From the truly elaborate to the surprisingly simple, there are several ways to enjoy the beauty of an indoor pond.
To describe the simplest indoor pond, all you need is a pot, such as may be used for large decorative plants, without drainage holes in it. Find a window that can provide some sun, place the container near it and fill it with water and plants. A small fish or two may be added if desired, and an internal sponge filter with power head can be employed to provide filtration if needed. While simple, this type of indoor "pond" can be truly beautiful. Good plants are small pond varieties like dwarf water lilies, small emergent plants like some irises or papyrus, and oxygenators such as parrot's feather or cabomba. Good fish would be small, colorful livebearers which will breed readily and help nibble algae off the plants, or fish from small, stagnant bodies of water such as bettas or gouramis. If kept well oxygenated through the use of many plants, almost any small community fish could be used, so long as they don't devour the plants.
A larger pond could be made using a little engenuity. Barrel or drum halves, wading pools, and even bathtubs have all been employed with varying degrees of success. You can camouflage the container by surrounding it with potted plants, thus making it more decorative and attractive. Or, if you have the budget and the desire, you could construct a pond.
There are different ways to construct an indoor pond. You could use a pre-fabricated pond shell, but those are usually made for sinking into the ground. It is better to use a pond liner and construct a well for it by stacking bricks or by using lumber to make a frame. This method would work just like any outdoor pond using a liner, but instead of digging a hole you are building up a frame. First construct the frame, making certain that the liner will fit it when it has settled into the shape of it. It should be larger than the diameter of the frame. Lay the liner across the frame and weigh the edges down with bricks, lumber, or whatever and begin filling the liner with water. As the water weighs down the liner, slowly relieve the tension by allowing the excess liner to let go of the slack. The water will fill the pond and the liner will shape to the form of the frame. Keep the liner edges in place by placing bricks, rocks, or wood on the border. Before beginning this type of project, make certain that the floor will support it. Water, bricks, rocks, and lumber weigh quite a bit and many buildings are not made for this sort of thing.
If you are certain you want the pond to be a permanent addition, you could even go so far as to construct a pond with concrete and rocks. In a pond of this stature, fountains or even a waterfall would be very dramatic. A variety of tropical fish could be kept in a pond that is this large, and if sunlight is provided via an electronic source or with a skylight or large window, a beautifully planted indoor pond could be kept year 'round.