My question is coming, but first some background. Here in the desert we use evaporative coolers. An evap cooler is a big fan that draws air across a wet substance, thereby lowering the air temp by 30 degrees or so. Works great on dry days and way cheaper than regular air conditioning. Problem is that sometimes it smells like a fishtank and blows that smell into the house. Not always so pleasant. To help with that and other potential problems, the system does a purge every so often, pumping out the water that is in the tank and refilling with fresh water. I have that water discharging onto some plants where it makes a small pool. The chickens sometimes drink there. Not a problem, might be a little higher in calcium and other minerals, but still just plain water. So I found some stuff made for putting in the water to help control the smell even more. The active ingredient is Ammonium Chloride. Very small amount, but I'm concerned about it being in the discharge water and the chickens drinking it. My research so far finds that Ammonium Chloride has many uses, including a supplement in cattle feed and certain human medicinal uses. It's also used for "contact explosives" whatever they are. Anyway, would a small amount of Ammonium Chloride be harmful to my birds? They have plenty of other fresh drinking water sources available all the time. The discharge water is only available once or twice a day. Also, I'm thinking about planting something in their run which is pretty shady most of the day. Do azaleas present any risk to chickens? I understand they're bad for horses. Thanks.