Another update!
Unfortunately, my pseudochalceus kyburzi ended up not surviving. They were wild caught, so likely caught and held in Colombia, then shipped to Florida, then to the vendor, then to my house within the span of a week or two. A lot of opportunities for stress along the way that made it hard to survive their hunger strike. They showed no interest in live shrimp, worms, frozen food, various dry offerings, or Repashy. Only flake surprisingly caught there attention, but only enough to swim slightly towards it, then quickly away. Parameters were likely fine as they're tailored to other Amazonian tetra.
Such is the way of the hobby.
I decided to replace that group with a large school of aphyocharax nattereri. They're known for being more aggressive than most tetra their size, so I thought they'd be a good fit for my hyphessobrycon species and aggressive botia. They shipped much better than the kyburzi too, arriving with fat bellies and eating immediately.
The botanicals haven't released much tannins to my surprise, so I'm likely going to add some more and rescape the tank to fit some more and remove plants that aren't thriving.
Additionally, I've been running an experiment with some heirloom or native strawberries (I'm not sure which, as they reproduce via runners and I found them growing in a clearing in the woods, but this area has had European settlement for 170ish years now). Some runners meant to propagate were left outside in a bowl and ended up submerged by rain in September. By October I was intrigued that they hadn't begun to rot, so added some grown floating on the surface of my betta tank. It's been weeks and they have excellent root growth, one has put out a few new leaves. So last week I planted some in the substrate of my 90 gallon and we'll see what happens! I'm expecting them to melt and become fish food though.