Copper in the waterer works!

I have a 3 gallon white plastic waterer. Actually I have four waterers, two in the coop, and two in the run. No worries about extra humidity in the coop or drips--they're both in pans and we live in the mtns of eastern AZ where the only time it gets even a little humid is during the monsoons in the summer. Even our snowy weather doesn't raise it much.

Anyway, one outdoor fount is in the shade, the other (the 3 gallon) is in a spot that gets several hours of sun a day--maybe three or four--in the middle of summer. I washed it last time and it had green algea growing in it. I wash them all every time I refill them, and this grossed me out.

I remembered somebody saying put copper in it--like a true copper penny. Then I remembered I had saved a couple pcs of copper pipe (maybe 3/4" x 3/4"? I'm such a crow.) so I got them, put them in when I refilled it. This week when it was time to clean and refill, the inside was...pristine. Smelled good, no algea, just ready to wash and refill.

It's nice that it worked on algae, but you may want to look into the safety of Copper levels.
It's one of those things that's both an essential nutrient and potentially toxic.
By using a piece of metal, you have no way to control the dose or know how much it is.
From the web I see that signs of toxicity to look out for include watery diarrhea and listlessness.

Heavy metal poison can also cause paralysis

I've been tossing a little First Saturday Lime into the water, and it seems to do a good job at keeping the algae at bay.