If you have water and sun, you'll have some algae. Is the algae growing
very fast and forming slimy floating masses? If so, it's likely blue-green
algae (which is actually a photosynthetic bacteria) and it's an indicator of
too much fertilizer running off from your lawn or garden into the water. If
the algae is growing fairly slowly, periodically empty the bath and let it
soak for an hour or so in a 5$ or 10% solution of bleach and water or scrub
it with bleach.. (Cover it while it's soaking so the birds don't drink it.)

Don't treat it with the copper based algacide used commonly by golf course
managers.

----- Original Message -----
From: "Gayle Benton" <gbenton at rockisland.com>
To: <tweeters at u.washington.edu>
Sent: Tuesday, May 27, 2003 10:13 AM
Subject: algae control in birdbath


> Hi Tweets,
> I have a little cement pool built into some natural rocks used solely for
> the birds and they love it. Even though it has a circulating pump, the
> algae builds up very fast. Does anyone know of something that will prevent
> this growth without being toxic to the birds? Thank you in advance.
> Gayle Benton
> Orcas Island
> gbenton at rockisland.com
>