When I first set mine up, I was emulating parts of lake Gatun, because that's where the 1st fish in the tank came from, and where I collected the plants.
Once I started seriously collecting myself, the river topograhy where I was catching the species I wanted was quite different.
There are really no aquatic plants in those more east Panamanian rivers, so in order to get the benifits of true aquatic, I plants realized they needed to be in a separate sump, and only terrestrial plants (similar to the way they surrounding the banks.in nature.
Some of the fish species from these areas are consummate detrius and vegetarian users, and use every bit of organic matter that falls in the river,
except the toxic plants lining the tanks surface. The fish make use of every bit of leaf litter, branches, sticks, bark, ...everything.
Below toxic plants like dieffenbachia, and arden Corton are the only ones spared.
These allow the sump to be, an "argueably" more pleasing part of the system as opposed to solely be a "deposito" for man-made gear, and banal media chunks.
It allows
for (along with the simple ammonia and nitrite elimination), the added benifit of "nitrate" reduction, not usuably afforded by normal means.
The sump below .
And some of the residents normally seen as snacks for cichlids and other predatory and opportunistic species.
lid
The current main cichlid tank below.