Hi all,
Matt, I've just got a good memory, and I remember your filter posts, and why you got the Eheim wet and dry, "solids" pond pump etc.. I like your approach, I think if you are going to go down the route of keeping fish like your Panaque, you need to do it like you mean it.
Algal scrubbers are mainly used for marine, because there are a very limited range of higher plants (macrophytes) you can use, really only Red Mangroves (Rhizophora mangle) and Sea grasses (Zostera, Posidonia & Halophila ssp.).
People do use Mangroves, but obviously the range of algae is much higher with Reds (Rhodophyta) and Greens (Chorophyta) using different light spectra etc. They both work the same way but in fresh water macrophytes give you the advantages of having roots and being much more efficient nutrient sinks.
I've got a lot of scientific papers etc. from the day job if people have specific questions.
cheers Darrel