Well the main tests that I run on my water are, I have have the test tube things that I test for ammonia, which of course is not really a problem in tap water. Then I have some litmus stuff that tests pH, hardness and a number of other things, I know the litmus isnt the best to use because its not REAL accurate, but my fish at home never even seem to stress when I do water changes, or even recently when I had to do an emergency tank move into a new tank that wasnt setup at all because of a 75 gal springing a leak.
What I have found is that if the chlorine level is high, the pH tends to be pretty high, so I just assume that the chlorine level is good since my pH level out of the tap ends up being at around 7.2.
This tank I have up here at work has a lid that covers all but a tiny hole of the top for feeding, and there are no air fresheners anywhere near me, nor people with perfume, (thank god im allergic to most perfumes) But that is a real good suggestion though, as far as chemicals getting into tanks, we just recently put an air freshener near one of my tanks at home, I'm gonna move it when I get there now. Thanks.
The betta seems to be feeling at least a little better now, hes not sitting actually ON the bottom any more, he is kinda hovering over it. I think he is gonna be alright, but will continue to monitor and do constant water changes until he starts perking up and swimming around.