Warm water temperatures and exposure to direct sunlight create ideal conditions for algae to grow in livestock tanks. In addition to making the water unattractive to livestock, some types of algae are toxic, and a severe bloom can clog overflow valves. Fortunately, you can reduce the risks of algae in your water tanks by making a few adjustments to your maintenance routine.
Move the water tank, if possible, to a shady location to reduce the likelihood of an algae bloom.
Scrub the water tank weekly. Use a stiff-bristled brush to thoroughly scrub the sides of the tank.
Add chemicals to prevent algae. Copper sulphate crystals, diluted in warm water and added to the tank every few weeks to once a month will reduce algae development. To treat 1,000 gallons of water, dilute 1.5 teaspoons of copper sulphate in 88.7ml of water. You can also add 2 to 3 ounces of regular chlorine bleach for every 50 gallons of water.
Keep animals away from the water trough for five minutes after treating. While the water is not dangerous to drink before then, allowing the water to sit undisturbed for five minutes gives the chemicals time to kill the algae and provides better results.
High copper levels are bad for sheep. Use the minimum amount of copper sulphate necessary to keep water clear.