Humidity/Temp Questions

Couple questions, I have a 20L setup with a UTH. I just bought a hygrometer you guys helped me find which alerted me to a couple problems. One, my humidity seems to be a little high resting between 65 and 75 and my temp is too low at 82 warm and 75 cool, if I buy a thermostat for my UTH can I crank the heat up or does it only work as a dimmer as in making it only possible to lower the heat. Plus if I turn up the heat isn't my humidity gonna run rampant since my UTH is right under my water dish? I saran wrapped most of the top except for a couple of openings for circulation, since before I had my hygrometer I had no idea what the humidity was and went about all the suggested steps to amp it up. Sorry for the lengthy post, you guys are always a great help, me just starting out and all.

What hygrometer are you using?

If I were you, I would put the water bowl on the cool side, or at least in the middle. I would also get a lamp dimmer, it lets you crank it up to over 100, even though you won't need it that high.
Now tell us what the humidity is after moving the water bowl, and tell us the temps after getting some sort of thermostat or dimmer.

With a thermostat, you set the heat at the desired temp. and it will maintain that temp. within a degree or three, depending on what kind of thermostat (and how much you spend on it) you get. A Johnson or Ranco will run about $75.00, but will have the least amount of fluctuation in temps. You can get a cheap one for about $35.00, but expect it to fluctuate about 4-5 degrees. Meaning when it turns on/off. A dimmer regulates the amount of current going to a device (I think) and will not turn on/off so, if your room temps. fluctuate you need to adjust it. That's why T-stats are better. Not sure about the humidity, you'll have to mess with the set-up a bit to get it just right. You can always add more air holes to reduce the humidity. I've just started researching this myself (get my ball in 10 days) so, hopefully someone else can add to this. I had to re-do my tub set-up like, 12 times to get it just right. BTW, I am using a T-stat (I would reccomend it to anyone)

It's a springfield precise temp digital tri view thermometer with hygrometer and clock from home depot. And thanks I'll pick up a thermostat asap