Muticlone Plus was announced in the UK last October. “It combines all of the revolutionary features of its predecessor with an inbuilt cartridge filter – and the streamlined design means the entire pool filtration system can be installed vertically, on top of a standard pool pump if preferred or on a base alongside the circulation pump. “–from press release.
Not sure if it would work for a large pond but a small pond would certainly benefit from the additional filtering as long as the owner is committed to cleaning or replacing the cartridge regularly. I wonder if you could input a bag of activated carbon in place of the cartridge?