I'm wondering what the rest of you do to try to control the algae population in your waterers. It's bad down here in south Florida. Any microbiologists out there? What the heck is the algae in all my waterers? I have given up on any sort of watering system that stores water for more than a day. I dump and refill all my waterers every day (sometimes both morning and night) and I STILL have to brush them out once a week (at least) or they get covered in black slime. Is this the toxic blue-green algae that everyone is talking about now (as a neuro-toxin that may be related to diseases like ALS and Alzheimer's)? If it is, kiss my sorry butt good-bye. I get algae-water splashed in my eyes and/or mouth once or twice a week. How do our birds survive drinking this algae-infested water? I am hoping that some biologist will tell me that our algae is not toxic.... Any takers?