Yes Mills A + B. It does it in all containers that receive tap water. I'm wondering if it could be sodium? 100ppm...
I unfortunately don't have any photos of 9 and 5 finger leafs on the same plant, but here is one plant I stuck in a 10g, topped heavily (and removed all the old fans) after the "tapwater choke" happened,just to see what it would do.
Yes that's the same plant. See how much the fan leaves change after a few weeks? Everything is normal then bam, new growth shrinks to half the size (The burnt tips if you see them are from forgetting to raise the light after repotting, not a related symptom).
And yes my guest bathroom is my research facility, lol.
Let me clarify this problem does not happen with RO. But I'm wanting to encourage my neighbors to grow when rec passes, meaning it has to be simple, and not everyone wants that hassle (especially me, there's no money in being the RO plug lol)