If you scrub their legs until they bleed and then apply tea tree oil, you are going to have some birds in pain..truly. Kinda needlessly harsh all the way around. You can soak their legs and feet in warm water, epsom salts and Dawn dishwashing liquid, scrub gently after soaking~not until they bleed!~ and then give them a soothing coating of castor oil. The castor oil can work as a preventative for your younger birds as well, as it's a natural insecticide.
I wouldn't do the soaking and scrubbing more than once every two weeks, to give the castor oil time to work. Reapply it when done with the soaking. When they have it so bad they are lame, it takes awhile to resolve from all accounts on this thread so you'll have to be patient. Castor oil can be purchased cheaply at any pharmacy and at Walmart. It is a mild antibiotic, antifungal and insecticidal that can help the scales heal and renew after the mites are resolved.
I wouldn't do the soaking and scrubbing more than once every two weeks, to give the castor oil time to work. Reapply it when done with the soaking. When they have it so bad they are lame, it takes awhile to resolve from all accounts on this thread so you'll have to be patient. Castor oil can be purchased cheaply at any pharmacy and at Walmart. It is a mild antibiotic, antifungal and insecticidal that can help the scales heal and renew after the mites are resolved.