I haven't tried it but would think you'll need quite a thick layer of Tropica to stop the pond soil diffusing into the water. That or a layer of sand in between. Just because of the Tropica grain size.
Using pond soil, I had bombastic Sagittaria subulata and Limnobium laevigatum growth. I covered it with gravel and there was no colouration, no algae and minimal lighting. I don't think I really changed the water. Some of it is very good indeed. It just depends upon the brand. Mine looked like a dark compost. Fantastic stuff.
I have Growise Aquatic Compost in mesh bags, mixed with a little coarse sand and some pea gravel. It's capped with coarse sand. Plants are growing well and no algae (only using fairly low light). Would do the same again happily.