There's always the risk of bacteria in cloudy RO water, so it's advised to rerun the system until it becomes clear. If you can't wait or your tank is full of cloudy water, it's best to avoid drinking it. Run the tank empty or clean reverse osmosis water filtration systems whenever possible before using the pure water again. However, cloudy water may also result from low RO water pressure or high temperatures. If this is the case, you can correct the problem by contacting a plumbing service for assistance.