Cleanitup is certainly an amazingly successful information resource already and credit to those who have worked hard maintaining and growing it.
I would agree that real names are vital to its future credibility. This would take some work , but would need an initial check before allowing a new user to make any posts. Perhaps the need to provide an address which can be third party verified. This would set cleanitup apart from most other forums - it has now got to the size where you can set your own rules rather than following the 'pack' as it were. This would instantly stop some of the rubbish posts and would help prevent deceptive posting.
Any users with a supplier affiliation could be indentified with a symbol in the left hand panel. This would automatically help other users to interpret any comments made by suppliers - such as this chap knows what he is talking about as he has had 10 years experience selling them or if promoting one item over another everyone knows the leanings that a supplier may have. This is done on many other forums and is not linked to advertising just for other users information. Something like a simple 'supplier' logo. If the supplier paid they could then have this as a link to their site.
Perhaps a section in the profile page where you can list years experience in your trade or various trades.
It would also be great to have a section guru who could provide authoritative information. This would be great for protecting those newcomers who need an answer being inadvertently mislead by other newcomers postings about subjects they know little about. For instance an RO guru, a chemical guru etc - this would help prevent expensive mistakes and would raise the credibility of the forum. This is similar to what Wikipedia has had to do in order to be able to be relied upon and taken seriously.
You could even have an ask the guru section for each subject. How you choose the gurus would be tricky though and why would they want to be a guru? Not sure how this could be done.
Obviously some threads are for fun and are not to be taken seriously, but others are dealing with product usage and would benefit from the credibility factor.
Another idea is to have an ask a supplier feature for those suppliers who pay for this. Users could post a question about products, technical issues, etc. and the supplier could interface directly with the other users - obviously as this is my idea you would be happy to waive the usual supplier fee