I'm currently using a typical chicken waterer with flat top. For chickens and quail, that works well enough to keep the water clean. But for pigeons, there is a pigeon sitting on top of it, pooping into the water. What kind of watering container/tray do you use for the pigeons to help keep their drinking water cleaner? DIY stuff is fine. I guess an idea I just had is a 2 liter bottle or 1 gallon milk jug that has holes in the side for drinking, small top that would not allow a pigeon to sit on it comfortably, but once the water gets low and it is not heavy, it would topple over. Thanks!