the first year I had clear water, running a UV filter, no alge what so
ever, the second year still running the uv filter, the water is clear, but
alge is now on the sides and rocks of the pond (im talking long strands of
alge) , now the 3rd year and I still have the alge with clear water.

UV will not do anything for string algae


How do I get rid of this alge and keep it from coming back.

I do have fish and no plants in the water.

Plants do help (the floating type with roots hanging down ( water hyacinth,
water lettuce) - they also help to provide shade (another big plus for
filamentous algae ) - you shoud have ~70% water coverage for shade such as
floating plants or lily pads to starve the stringy ( filamentous ) algae for
sunlight

The only filter I have is a large sponge attached to my pump.

A bio filter will work better for you, depending on pond size to keep your
water parameters better


The pond does get sun.

I live in Toronto, Ontario, Canada

Oh.. I have other friends who also seem to have this problem which started
last year also, and they look to me to solve their problems also.

Any suggestions ?


Gale :~)