Hey Big,
It's great that you are really into this and that's what it takes to grow good weed yerself....But one thing to keep in mind is that it is a very resilient plant. The fans going on and off I'm not sure how much that would matter.....Mine come on with the lights and then go on with the lights. (Except my intake fan that stays on always.)
As far as the lighting goes whenever dealing with cfl's ....the more the better....As long as leaves aren't dying and turning yellow from lack of light then you are fine.
The yeast and sugar....Im assuming it's producing co2....If it's helping then keep doing it.
Rain water is a good Idea (not from a drain spout) it's just hard to keep on hand and hard to collect, I just get distilled water from the grocery store when we go.....You should only water every few days....So I just buy 3gal or 4gal when I need to.
As far as the PH tester i got one.....Its works. But Ive never really had a problem with ph. But i know that 6.8 is good....Lemon Juice? Google it....