Quercus Robur wrote:

I am sure this has been posted many times, so please excuse me.

A while back I saw a post about using UV filters to remove algae. This
puzzles me. Algae thrives on UV from sunlight,

Sorry I missed the original post.

Using UV to kill algae may sound like BS, but read on.
Ultraviolet light kills many things in the water and is effective on
algae as well. Some commercial systems (Pet shops and commercial
fish keepers.) use large amounts of UV and kill lots of junk. See
chart at the end of the article:

http://www.aquaticeco.com/index.cfm/...Detail/ttid/80

Regards,

Hal