Fortunately, it can be simple to clean a bird bath without scrubbing if you follow the proper steps. This technique will take 20-30 minutes total, though for much of the time you'll be able to attend to other tasks as the bird bath cleans itself. While the basic technique is suitable for bird baths of any material, it is most effective on concrete bird baths. If your bath is unique and delicate, take precautions to protect it before trying this technique.
Materials you'll need…
Hose with pressure jet setting
Black plastic trash bag
A very dirty bird bath!
Step 1: Dump the Water
The first step in cleaning a very dirty bird bath is to get rid of the contaminated water. This water is often filled with organic material such as feces, algae and dirt, and it is safe to use to water nearby flowers or plants. Dump the water out in an area where it will be recycled to help the rest of your garden, but treat the basin of your bird bath carefully to avoid damage. If the basin of your bath does not detach, simply tip the pedestal to drain the water onto nearby plants or grass.
To safeguard your birds from this dirty water, avoid dumping the basin near bird feeders or spilled seed that ground-feeding birds may sample.
Step 2: Rinse the Basin
Using the pressure setting on your hose nozzle, rinse the bird bath for 10-15 seconds to remove any stuck on debris, feces or loose dirt. For a very dirty bird bath you will not see much change from this rinse, but removing surface material will help the bath be cleaned more thoroughly. If your bird bath has a textured basin, be sure to tilt your hose at different angles to get in every space.
If your bird bath has a delicate surface, avoid the highest pressure setting that may loosen a mosaic or chip a surface finish. Instead, use lower pressure or wipe the surface lightly with a soft sponge.
Step 3: Refill the Basin
Refill the bird bath basin until it is nearly, but not quite, full. It is essential to fill past any obvious dirt or algae lines to ensure that every affected surface will be cleaned, as only areas covered with water will be cleaned. Check that the basin is as level as possible to ensure uniform cleaning. If desired, you can leave the basin on the ground to do this, but it will be just as easy if it is on its pedestal.
Step 4: Add Bleach
Carefully add a generous cupful of bleach to the water, taking care not to spill the bleach onto nearby plants or grass. When adding the bleach, pour it slowly around the entire surface of the basin to mix it thoroughly with the water. If desired, use a stick or twig to mix the bleach with the water.
The amount of bleach you add can vary, but do not add more than 1.5 cups to a basic bird bath. If you have a very shallow bath less bleach will be needed, while more bleach may be necessary for a deeper or excessively dirty bird bath. Basic chlorine bleach is most effective for this step, but if you prefer a green-based similar product, you can adjust this cleaning technique for your preferences.
Step 5: Cover the Basin
Cover the entire bird bath basin with your black plastic trash bag. This will keep the birds away from the bath so they do not drink or bathe in the chemically treated water, and the black color will absorb the sun's heat to heat the water and clean the bath more quickly. Pull the bag thoroughly over the basin and down the pedestal so it will not blow away in a breeze, or if you are cleaning a ground bath, weight the bag down along the edges to keep it in place.
At this point, leave the bird bath to soak for 10-15 minutes. This is a great time to refill or clean birdfeeders, make hummingbird nectar, check a birdhouse or tend to other birdy tasks in the backyard. If necessary, you can leave the bird bath to soak for far longer, but for thorough cleaning a minimum of 10 minutes is recommended. Very dirty bird baths may need longer soaking to be fully clean.
Step 6: Remove Trash Bag
When you remove the trash bag after letting the bleach water soak, your bird bath will look like new. If there are still remains of algae or scum in the basin, replace the trash bag and let it soak longer. Otherwise, discard the trash bag or save it for reuse – the same bag can be used every time you need to clean your bird bath.
It is important not to leave the bird bath untended at this point. The clear water and full basin can quickly attract thirsty birds, but the high chlorine levels in the water can be fatal. Instead, drain the water immediately. Avoid dumping it directly on grass or plants, but feel free to dump it on weeds or in an unused area of your yard. As with your first water dump, avoid draining the chlorine water near bird feeders or spilled seed.
Step 7: Rinse the Basin
After dumping out the bleach water, use the pressure setting on your hose to thoroughly rinse the bird bath. A rinse cycle of at least 1-2 minutes is recommended to dilute any remaining traces of bleach and make the bird bath safe for drinking and bathing. As before, tilt the angle of your hose to ensure you get into every nook, cranny and crease of the basin so every part of the surface is thoroughly rinsed, and take care to protect delicate surfaces.
If you aren't sure when the basin is properly rinsed, stop and sniff the surface of the bath. If it smells strongly of chlorine, more rinsing is necessary. A faint chlorine scent is acceptable, but it should not smell as strongly of chlorine as a pool would.
Step 8: Sun Dry the Bird Bath
Allow your freshly cleaned bird bath to thoroughly dry in the sun. This will further discourage algae growth and keep the bath fresh for a longer period of time, and it will help sterilize the surface against bacteria or other contaminants. On a hot, sunny day, the basin can dry in just a few minutes, and you can use this time to put away your cleaning materials or finish refilling birdfeeders.
If you do not have the time to allow the bath to thoroughly dry, it is acceptable to skip this step.
Step 9: Refill the Bird Bath
Refill your freshly cleaned bird bath with cool, clear water for the birds to enjoy. Properly filled, a bird bath should have a depth no greater than 1-2 inches so birds can easily drink and bathe. If your basin is too deep, consider adding stones to give birds a shallower area to use. You can also attach a dripper, mister or bubbler to attract more birds.
Voila! Your bird bath is clean and safe for the birds, without using any scrub brushes or elbow grease. With the bleach treatment, the bath will remain clean for several days, and you can keep it clean even longer by draining, pressure rinsing and refilling the bath daily before it will need another thorough cleaning.
Step 10: Sources
This information was taken from http://birding.about.com/od/birdingsupplies/ss/How-To-Clean-A-Bird-Bath-Without-Scrubbing.htm
This was not my plan but i used it and it worked create. Reposted on Instructables to help others out! Take care.