"Get Rid Of The Grime. 
Dirt and debris wear on the fountain's surface. Once a month, bail out gritty water (or siphon it off with a wet-dry vac); then wipe the interior with a soft cloth or sponge. Scrub off buildup with vinegar and a soft bristled nylon brush; wipe clean and refill.

Put On Socks. 
Slip an old nylon stocking over the pump and its intake to keep out stray dirt.

Fight Buildup.
 Each time you refresh the water supply, add a clarifier to deter algae growth and a scale and stain remover, following the label directions on dosage (it depends on your fountain's capacity). Double the normal amount if you notice algae or scale that persists. In warmer months, when algae grows more readily, add a time-release algaecide in tablet form about once every three weeks.

Don't Let It Run Dry. 
Your pump could overheat if the water level's too low, so keep an eye on it, especially if you've had a string of hot, dry days.

NEVER USE Chlorine.
Fountain pumps aren't designed to work with concentrated levels of chlorine, but if an algae bloom won't die down, add 1/4 cup of distilled vinegar for every 5 gallons of water, and run the pump overnight so it circulates long enough to disinfect the entire system". You can also add shiny copper pennies to oxidize the water and fight algae growth. 

Reference:
DISHNER, Jackie. "Five Tips To Keep Your Fountain Running." This Old House. Thisoldhouse.com, n.d. Web. 02 Apr. 2014. <http://www.thisoldhouse.com/toh/article/0%2C%2C20209545%2C00.html>.

"A wonderful way to enhance the beauty of your garden is to install a solar powered garden fountain. Compared to traditional electric fountains, solar powered garden fountains allow you to be gentle on the environment and to reduce your running costs to practically nothing. Maintenance is simple, too, with no wiring to look after. And yet a broad range of prices and styles are available.Setting up a solar powered garden fountain is easy and care of these fountains is minimal once installed. Want to use your solar powered garden fountain at an evening party? One option is to install a battery backup for working when the sun is not shining. Weekly maintenance is simple. Panels may accumulate dust or dirt, which can easily be wiped off.

Once installed, if you find the pumps' power is not to your satisfaction, you may need to reposition the solar panels somewhat to increase maximum solar energy. It's also possible to add extra solar panels if you want to increase power to the pumps. Just note that water jet intensity will fluctuate according to the presence of sun throughout the day, and of course be lower on cloudy days.

You can buy solar powered garden fountains with panels and fountain all in one unit, or purchase a model that allows you to place the panels at a distance, connected by a cord. Either way the panels' position needs to be where they can get maximum sunlight. If setup is separate, this allows you to place the fountain in any location, sunny or not.

The best benefit, once the solar powered garden fountain is installed, is sunlight is free and summer time use has no limits. Since there is no need to place the fountain close to an electric supply, installation can be at any distance. This is especially ideal for large gardens.

The only disadvantage is total dependence on sun; solar powered garden fountains work best on bright sunny days. Performance will slow down on cloudy days. Once the freezing chills of winter arrive, it's best to move the unit indoors to prevent damage from snow and frost. Extremely low temperatures could crack the bowls of the foundation.

Solar powered garden fountains are designed for sunny locales with mild winters. They come in a variety of styles; some float, others are placed on solid surfaces, but are the most cost-effective way to enhance your garden, harnessing one of the planets most renewable energy source, sunlight. Make your garden truly green, go solar". 

Reference:
Hessman, Scott. "New Gardening Trends: Solar Powered Garden Fountains." Yahoo Contributor Network. Voices.yahoo.com, 16 Nov. 2011. Web. 25 Mar. 2014. <http://voices.yahoo.com/new-gardening-trends-solar-powered-garden-fountains-10428209.html?cat=32>.

"A beautiful outdoor fountain can make a great focal piece for any garden or patio. Through proper care and good cleaning, your garden fountain can run smoothly through the test of time. There are several types of outdoor fountains to choose from depending on your personal taste, the size of your patio or garden area and how much time and maintenance you are willing to invest.

Outdoor Fountain Care 101
Keeping your outdoor fountain clean is just as important as maintaining the proper water level. Routinely wiping the inner bowl of your outdoor fountain with a non-abrasive cloth not only keeps it looking shiny and beautiful, but also prevents the build-up of dirt and dust. Additionally, it is vital to remember to refill and clean your outdoor fountain pump on a regular basis as a dry pump will most likely result in the purchase of a new one.

Cleaning your Garden Fountain
Cleaning the bowl and pump is essential to the life of your garden fountain. The bowl should be emptied and lightly scrubbed with a toothbrush and dish detergent every one to three months. Before beginning your outdoor fountain cleaning, be sure and consult your manual in case your garden fountain requires a special cleaning method. For some garden fountains, algae additives and filtered water are needed to break down the build up of mold and calcium.

Outdoor Fountain Pump Maintenance
Before removing the pump, consult the manufacturer’s guide on proper cleaning and detaching methods. Once the pump is removed and opened, place it in a solution of vinegar for an easy-clean solution.

Preventing the Growth of Algae
Along with replacing the water on a monthly basis, you can also purchase an algae cleaner to decrease the growth of algae and keep the outdoor fountain’s water fresh. In addition, it is important to remember that algae, much like all growing organisms, experience increased growth when placed in well-lit areas. If algae continues to be a problem for you, you might want to consider moving your garden fountain to a shady area.

Appropriate Water Levels for Your Garden Fountain
As mentioned earlier, water levels are key to maintaining a healthy pump. The water level of your outdoor fountains should be checked daily, with small amounts of water added at each interval. Each month, you should drain and re-fill your outdoor fountain with fresh water to prevent stagnant water. Additionally, dry summer months can cause the water in your outdoor fountain’s bowl to evaporate more quickly, so be sure and check the water levels more frequently.

Let it Snow: Winter Outdoor Fountain Care
In seasonal climates and severe winter regions, outdoor fountains should be transported indoors to prevent cracking and freezing, especially marble garden fountains. Should removing the garden fountain from the outdoors prove to be too great of an undertaking, drain the outdoor fountain completely, dry it with a non-abrasive cloth and place a garden fountain cover over it as a protective shield from the weather".

Reference:
"Tips for Year-Round Outdoor Fountain Maintenance." Improvements Blog. Improvementscatalogblog.com, 15 Oct. 2012. Web. 06 Mar. 2014. <http://www.improvementscatalog.com/RoomForImprovements/tips-for-year-round-outdoor-fountain-maintenance/>.