Opaque or Semi-Transparent
Whether you go with a solid color bucket or one that you can see through, the fact remains the same; you're going to have to clean it. Algae and scum can contribute to disease and possibly affect the operation of automatic drinkers. I have used both opaque and semi-transparent reservoirs, and there are pros and cons to each. In my testing and trials, I have come to prefer the semi-transparent reservoir. In all actuality, the semi-transparent probably grows algae a little faster. The benefit though is that you can see it building up, offering a visual reminder of the need to clean it. The other advantage of the semi-transparent reservoir is the ability to see the water level. That's pretty important!