The beauty of a water garden is that they require very little in the way of care and upkeep. Fertilize sparingly using a fertilizer specifically made for water plants. If you find your garden getting low on water, just top it off with the hose as needed. The biggest problem in maintaining a water garden is algae formation. Placing a variety of floater plants as well as submerged plants will greatly reduce this irritating problem. Another problem with water gardening are mosquitoes. Mosquitoes are naturally attracted to stagnant watery conditions and can be a real nuisance. By adding a "bubbler" to your container, you will keep the water moving. It is a good idea to drain your garden every couple of months, or as needed when pots start to look muddy. Carefully remove plants and scrub container thoroughly with a stiff brush. Then fill with water and place your plants in container once again. In colder climates, your water garden will need to come inside, as it won’t survive the cold temperatures.
I hope that you decide to try this project for yourself as it makes a lovely addition to any backyard landscaping. It's a fun project for the "do it yourselfer" and can easily be created in a day.