This is SO danged embarassing! I was watching the fish after the r/o water change and realized I was seeing ammonia toxicity in their behavior. I had done every chemistry EXCEPT ammonia and they were fine. Bingo: ammonia off the map.
I realized I'd washed out the filter sponges a LOT and may have trashed what biofiltering I have in the back. I also took out a couple fish and changed the water [non-r/o] again. Then everything started to look normal right away...
Gonna do another non R/o water change today and keep watching.
Here's the current fish list:
1 Dwarf blue guorami [2 inch]
4 Rasbora [emerald green-eyed @ 3/4 inch long]
2 Dwarf Corys [Each 1 inch]
3 shrimp left.
It's a 12 gal Nanocube.....
Figs [Hanging my head...