Cleaning green, corroded copper pipework

Hello everyone,

There is some very corroded copper pipework in my house, put in by a so-called plumber before I bought it. Large areas are green around each soldered joint, obviously caused by not wiping the joints properly.

They are very unsightly, apart from the fact that they could become worse and penetrate today's thin-walled pipework. I have tried everything I can to remove and treat the corrosion, but nothing seems to work and of course the rather waxy finish from the flux doesn't help.

Any ideas please?

Thanks,
Alec.

Isopropynol and wire wool?

Fine wire brush (with brass wire filaments)