We use citric acid to cut mineral build up on our watering line nipples in the layer barn. The birds actually drink more when it's being added to the water. I think they like the tangy taste.
It's also used in broiler production to improve feed conversion ratios. It improves mineral uptake by the birds.
A general rinse is all you need.
How much citric acid (powder/crystals) do you ad say, per gallon of water?