Invalid users (eg spammers)

[VK4ADC]

There has been a recent rise in "new users" creating a login on the Forum, and while not wanting to inhibit genuine amateur operators joining the Forum, they are creating additional workload.  Each 'new user' has to be manually IP-checked to see where their IP address is actually located, their supplied email address checked against known spam addresses, and if they seem to actually be within VK (or ZL,..) then whether they are arriving via a VPN endpoint here.

I can tighten up the registration questions a bit to make it harder but possible users could 'Google' for an answer and at least put in a credible guess to get access.  I can also make it a manual-only registration : each user has to be manually activated but the same workload is involved.

There is an option to let them join but not be able to post without manual moderation involvement, at least until they have shown to be appropriate users.  

I am open to suggestions as to protecting this resource from spammers and hackers without inhibiting valid users joining.

Comments ??