if they are serious about their forum, they should have been atleast for a while, limit the maximum posts a user can post in day. Best choice is just to pick which users they will be paying according to their ranks, post quality, etc.
The problem is, if they take these measures, then nobody would post in that forum because pay/quality rate is not good enough to attract good posters.
Right now they can only attract spammers and they even fail at it.