compromise water parameters for cherry and CRS shrimp

[beanbag]

So originally I had a tank with cherry and Amano shrimp with pH mid 7's, GH 6 KH 5 TDS 210-230.  I wanted to add some CRS, so I started adding new water with lower KH, as well as a thin layer of a buffering substrate.  After 1-2 days, I got the water down to ph 6.9-7.0, GH6 kH 3-4, and the neos seemed to be pretty happy.  I added the CRS and continued to slowly keep changing the water over the next few days till it is now ph 6.7-6.8, GH 6 KH 1, TDS 180.  The CRS are grazing at full speed most of the time, but the neos seem more inert now. 

I've seen minimum recommended kh values of 2-3 for neos, but I thought shrimp didn't care about the kh value as much as the pH (and stability)

Should I start raising the pH / kH again, or maybe just wait it out to see if the neos get used to it. 

To further complicate matters, my tank is ecologically changing due to:

new water parameters

started gravel vacuuming less since topping with the buffering substrate

I actually see some patches of biofilm growing on the glass now

Irregular feeding pattern as I try to figure things out

weather is changing - getting a few cold days now, so I'll be installing a heater shortly

[jayc]

I would stop and maintain it as it is now and see how the Neos adapt.