If you're just after nutrient export, stick with the Chaetomorpha. The super fast-growing Caulerpas species (namely C. taxifolia [feather Caulerpa), C. racemosa (green grape Caulerpa) and their variants) are also very good for this purpose. You'll want to prune them regularly, and freeze any prunings for 24 hrs to be sure they're dead befor disposal, however. As long as no bits of the plant get to the DT, and the stuff doesn't go sexual (warning signs are easily seen), it won't grow there.
The reds such as Botryocladia (red grape), Halymenia (dragon's tongue), look nice, but are much slower-growing, and require dimmer lighting, as they tend to "brown out" under intense lighting, altho they do grow a bit faster.
We run live macro in most of our DT's, and it looks nice, and is a huge aid in water quality (we keep Scorpaeniformes pretty much exclusively, which are a big bioload).
HTH