Not sure about the calcium reactors, havent read up on those yet. lol
If you dose kalk
it will help with your ph, I have low ph and while i was dosing Kalk
it was very steady at 8.3. But I stopped dosing cause of some coral issues and now its back to a stable 7.9-8.0 :-(
As far as the skimmer, I have mine set so that it skims a dryer skimmate, means less dumping of the cup too as well as a "meatier" skim. Thats something you just dial in according to your preference really.
Hope that was at least a little helpful! lol