Hello and welcome
Unfortunately it is not only welcome to a care's forum, but also welcome to the world of the Internet.
Spammers [eg porn, drugs, finance, etc] and trolls [badly disturbed people who try to divert the forum to their own agenda] do for their own reasons attempt to post material on all forums.
You have been unlucky in that you have joined at a time when I am banning loads of would-be spammers before they can post their wares.
Unfortunately, as a human spam filter, I do need sleep.
When I'm not around, other moderators will move offensive material out of the public area.
This is the record of spammers I have banned the past week - note that today there have been 16 so far and it is only 07:00 hrs.
There are thing that a forum can do to minimise spamming:
1. not to permit registration before we check the identity
2. to amend the registration process
The Alzheimer's Society has chosen to do neither of these because either - or both - might cause problems to a genuine carer wishing to register and needing a reply to an urgent question very quickly.
Spamming [and trolls] is something we have to live with.