Do you have access to UPS/DHL/FEDEX?
You should be able to find a UV there...(if your handy you can make your own froma germicidal lamp and a sealed box, just NEVER LOOK AT THE LIGHT WHEN IT'S ENERGIZED!
Ok, remove plants and cover the pond with an opaque material for 4-5 days so that NO light enters, keep the filter running, if possible use a pre-filter material (poly-fil, filter socks, felt)(as hankn suggested) and clean it daily. The lack of light will kill most of the algae and break the growth cycle. After the last day do a large W/C (50%-80% if possible) cleaning the botom as you do it.
Replace plants and add as many as possible, placing them in gravel or rock filled baskets or cages so water can circulate thru the roots.
"how can i put lights over a pond?" Why?
Shade would be nice, but plants (floating broad leaf type) should help.
Dr Joe
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