1. I have IntelliPH which allows me to control the intelliChlor.
2. I run it 8 hours a day (but I cut back to 7 hours just in case it was due to the amount of time i was running the system).
3. I have a Taylor 2005 kit with a Taylor DPD-DFAS for chlorine (basically turning it into a Taylor 2006 kit) AND a ColorQ. (These two differ on PH, but I trust the Taylor Kit more).
4a. The staining has been slowly developing over the last 3 years, I thought I had it under control until around February it started getting worse (I assumed is was because I wasn't controlling PH good enough so I purchased the IntelliPH to better control PH). I believe the staining is calcium buildup. I will post pictures in a couple days we have had tons of rains the last couple days, so right now I am just trying to get the rain water out of my pool. I do not attribute the staining to recent events.
4b. I do not have a heater.
5. Not recently, about 1.5 years ago I was told to use phosfree (which I did, but it seemed to make controlling my chemicals worse so I haven't added anything since). Last year I also had a pool guy improperly maintain my pool. He was treating it like a chlorine pool, even though it was a SW pool (I was out of town for a couple months). When his boss got on him he came and dumped way to much salt in the pool and I had to partially drain it because the TDS went through the roof and the Salt content was like 4800. I immediately fired them because they wanted to charge me to do a partial drain of the pool due to my high TDS which was because their tech over salted the pool.

I believe the chlorine is because I am running the pump too long and the temperature/Sun isnt hot enough. Generally in the winter months i only run it like 4 hours, maybe I jumped the gun on increasing the pump run time, because I was trying to dial in the intelliPH dosing and the percentage i figured wasn't enough so I increased run time, when i should have just increased dosage percentage.