My water parameters are rarely checked now unless I encounter a problem.
We have a fairly hard water base that keeps the PH almost at a steady 7.0 with a slight variance. Not much of one though. I do regular maintenance on my tanks to keep the other levels in check.
I keep all of my tanks at 78 degrees (fahrenheit, not celsius).
For now, my new ITs and NTTs that may be up to 4" are in my 29 gallon quarantine tank. Once they move out of there into 75 gallon growout tank the parameters will be the same, and the gravel in the tank is a natural brown color with other natural looking decor (some rocks and some wood). My lighting on the 75s is more on the lighter side.
Stability is moot for now. My dats are all new and small. I lost my former dats a couple of years ago to improper quarantine measures coupled with a heater malfunction (got too hot when I went to work one day). Well, aside form the one that bit the rays tail off killing the ray and itself. That was my first dat too.