Yes this is a bit of a n00b question and I've had a quick search, however since the Apexi filter is a dry-fibre type I didn't know if what I read would apply.
Basically, do you need to clean Apexi filters and if so whats the best way? I don't want to go putting water on it just to have it clump up the fibrous stuff and it doesn't need oiling - it also came from Japan so all the documentation is in Japanese. A lot of things I have found say they are almost maintenance free and last a lifetime but surely they'd need to be cleaned every so often?