Rotundifolia and indica, both just go poop on me. Either collect algae or vanish haha because the "easy" ones done well and they're the only ones I can get cheap locally, everything else I have to order online and I can't justify paying more just to know it'll likely die off for me.
Took 13 tries to get duckweed to live
I've tried rotala from another hobbyist locally a couple times and store twice.
Took 5 times to get java ferns going, and only got going for me once I got them from a local hobbyist and started dosing potassium on top of my normal fertilizer lol
Sometimes some plants can be that way. I don't write it off as a failure of a plant until after 4x failing lol its funny because a local friend of mine does fantastic with ludwigia, we have similar/same water source and both low tech and I can't keep that alive under water either!! Grows like a weed out of water for me though
he can also grow pogostemon helferi and I can't haha.
As for the oven baked clay, these are the first times I've ever played around with this type of clay. In the past was always just the reusable clay or sculpting clay. I definitely prefer these, but we bought it for my kid so these will be the last I use because I want him to enjoy it, not mom use it all on him
My plants that don't work for me:
Water wisteria
Water sprite
Bacopa caroliniana
Bacopa monnieri
Ludwigia except "orange'
Pogostemon helferi
Hygrophila strict
Hygrophila corymbosa
The funny thing with bacopa is that I can grow bacopa australis like a weed, stuff does fantastic for me, but not the others, especially caroliniana which I can't even grow emersed