Pigs need plenty of clean water to cool their bodies and grow well. Your pigs will not get clean water from a tank or trough. If you put water in containers, pigs will trample it/contaminate it, which can lead to worms and diarrhea. Water requirements per animal; (3 months -5 liters) {lactating pigs are 25 liters} [1 year is 12 liters]. Pigs will increase their intake if they drink a lot of water.