My uncle and I both own chickens in the Phoenix area. Him for 5 years and me for going on 2 years. Something that we've both experimented with that has worked greatly is acid water. We've both had chickens with the mucus and watery substance coming out of their mouth and gave them 10 ml of acid water a day and we watched them all get healthy and survive within 3 days. My uncle has a Kongen water machine that produces akaline water, but offers water at different PH levels. The acid water is PH 2.5 and highly acidic. Its saved four chickens now between the two of us. And I currently have a girl on the acid water. If you don't have a machine. My recommendation would be to go to your local "Water & Ice" or local water store in your area. Often times, they have one of these machines and you can buy the water from them. If the chicken is freshly sick with the mucus situaition than only 10 ml once per day and if the chicken is really bad than 10ml twice a day.