Only two dead after another day. Relative improvement. Second opinion on tank water agrees with my home tests for pH, ammonia, and nitrite. Store did not offer the other tests. Two new egg laden neocaridina females seen this morning. Baby shrimp in bottom right corner plant cover from neocaridina that arrived with eggs. Dozens of shrimp however still huddled on heater. I'm getting mixed messages. Added a heavy metal remover to the filter but that seems very very unlikely with baby shrimp still alive.
Plan is to go hands off for at least few days, preferably a week, to let current conditions ride out. Unless I get a different opinion on why I should continue doing water changes at this point.
Many thanks for the thoughts up to this point.