I recommending decontaminating your wing atleast once a year or as needed. Fill with fresh water + steramine. Otherwise everyone's advice is spot on.
I don't want to open a new thread, because this might be Interesting to the OP aswell:
As steramine is not really available in Europe. Does anyone use virkon S for Desinfektion of mouthpeace and wing?
Disinfect them why?
I’ve been diving a BP/W for over 15 years. I thoroughly soak & rinse my wings (when used in salt water) but I’ve never disinfected any of them. Not once. I’ve never had a single issue.
I also give the inflator a very thorough rinsing after every trip. I have a hose adapter that allows you to flush with water via the inflator. Tobin @ DSS used to sell them. It’s awesome.
I do give the exterior a good UVTech treatment once a year. It protects them from the sun and really helps keep them looking brand new.
To the OP ... no, you don’t have to get them ‘serviced’ annually.