What kind of filter do I need with underfloor heating?

[redhexagonal]

So I have a combi boiler and two zones, one is underfloor heating and the other goes around 9 radiators. There has been alot of black sludge blocking the heat exchanger the last few years. I am planning to get a filter on the system and I was recommended the Magnaclean Pro 2. However I dont think it filters non magnetic debris like the bacterial stuff in the underfloor which I can see has gummed up the flow meters on the UFH manifold. Should I be getting a filter that does magnetic and non magnetic filtering or is the Pro 2 sufficient? If so any recommendations for a particular filter? (I should add, this has to go on the flow because there is no room on the return)

 

[muggles]

If you're getting bacterial buildup a good dose of biocide is what's needed

 

[Mr Chibs]

I have similar system, and I dipped the filter to have a butchers what was going on after a few years of service.

Cleaned out magnaclean filter water is yellow/greenish

Thought I'd clean out magnaclean filter on my combo boiler (intergas rapid+ 32Kw) Was a complete new install 3 years ago. The system had inhibitor and from what I remember a biocide for the UFH. There was hardly any crud on the magnet, but the grey strainer was slightly green stained bit like...

www.diynot.com

I recently dosed it again with Sentinel x700, through the filter housing, opinions seemed to be it was OK, I'd like it clearer, but hey ho.

There was very little crud on the filter, so at least that's doing it's job.