Hydro Cloning, Stabilizing water PH??

I'm using a home built misting cloner box and I'm having trouble getting the PH to stabilize, it steadily goes up as the days go on. Yesterday I left it at 5.2, figuring it would go up a little and today, less than 24 hrs later, it was up to 5.6.
Three Questions:
1. Is it normal that the ph steadily rises?
2. Is it possible to get the ph to stabilize?
and
3. What's an ideal PH to keep the water?

im about to start my own aeroponic grow and i can already assume what every experienced grower is thinking and its that growing weed hydroponically or any other system that is soiless is difficult, and your going to have problems all the time until you really get the hang of it (or it becomes rutine). So my advice is to take a chill pill and just take care of your grow 24/7 a day. Eventually youll find a rythm that you will get used to and it will grow on you. other wise your going to have to do everything soil or start buying from a dealer again.

shit im high and i cant wait to build this aero system! lol PUMPED