There are products out there the “make a bird’s plumage shine”. You don’t need these. It’s a waste of money and really ads nothing beneficial to a healthy bird. Birds have natural oils on their skin and feathers to keep the feather barbs together and to keep it managed. Your bird will take a bath when they feel they need it. As long as you have a bath available every day for them, a simple water bath alone should be good enough to keep their plumage healthy. If there is something off with their feathers there is probably something you need to consult a vet about. So don’t use any unnecessary products on your bird unless specified by your certified avian vet. Save your money.
