I don't use planters.
I just take cuttings of terrestrial plants and dangle them with the stem in the water,of the tank, but with leafy parts draped on the rim, or on the tops of the tank, and also can be zip tied to and along the plumbing, until they set (after a while they cammofauge PVC plumbing.)
With vines (like the one below), roots dangle in the water and the vine travel along the plumbing above.
I do the same with Dieffenbachia, where the cutting is dangled, stem end and roots in the tank water, but after a while, the stem gets so massive, it just lays on the tank top, and supports the entire 5 ft plant.
One of the stems on a Dieffenbachia above, it is as thick as my wrist.
With the mangrove trees below, I filled bamboo stem cuttings (logs) with sand, stood them in the back of the tank, and jammed the mangrove pods in the sand.
Now that the saplings are surpassing 2 ft tall, the roots are starting to break out of the confines of the bamboos hollow logs, but seem to manage to remain upright in the tank, anyway.
The free range roots do get a little unruly in the tank, but my cichlids seem to take to them .
and kind of remind me of the way terrestrial trees send roots into the rivers that I collect and snorkel in, and where fish like cichlids often hang out
An Andinoacara hanging out in the tree roots, on the last minute of the video below.
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