
Looking further, they added something called Viglink - it Opts you in automatically on install and sends any affiliate commissions when people follow a link and then purchase something to the forum software developers (PHPBB) to continue funding the project.
BUT I also discovered I can Opt out and choose to have the commissions - which might just help towards another problem! Funding the site.
Soooo....
I don't like having advertising but it becomes a reality when you run a website unless you pay for hosting yourself or have sponsors. The forum hosting is around £250 per year at the moment and the poultrykeeper website £1800 per year (it has more traffic so has a 'business' plan). It doesn't help having to pay VAT on top of the charges as well.
Also, the forum falls over from time to time (behaves erratic) at peak times because the shared server runs out of resources or more correctly 'we are being limited so we don't impact other users'. The next step up is a 'Virtual Private Server' and yes, you guessed it, I'd need to spend more

Until now, poultrykeeper (.com) plus a few donations we've received has covered the forum running costs but traffic is down this year and there are more and more people using ad-blocking software and less people clicking on adverts. I haven't checked for the last few months but I'm getting closer to paying in myself.
I was thinking of adding Google Ads at the bottom of each page - but last time I did this, I think it generated a couple of pounds per month... We got a Sponsor one year (Verm-X) which was also very welcome. This Viglink scheme is certainly worth trying out.
Let's see how it goes and if it becomes too intrusive, or only generates a small amount, I'll disable it and go back to the drawing board.
Tim