Narrowly on the matter of “clean feeders”, I’d recommend people (particularly of interest to those in the UK) check out Finches Friend. They make feeders design

Narrowly on the matter of “clean feeders”, I’d recommend people (particularly of interest to those in the UK) check out Finches Friend. They make feeders designed to avoid the spread of disease (primarily trichomonosis) and their blog posts are full of related information. https://www.finchesfriend.com/ https://www.finchesfriend.com/