Kind of New, a couple quick questions!

[kiasyd]

Hi everyone! I've been lurking the forums for a while but I haven't really posted anything. Anyways, I've already got a Normal KSB (That's a picture of him as my avatar!) and I was looking into getting a Ball Python soon (snakes: you can't have just one!). After doing a few months of outside research and browsing the forums here, I feel like I've got almost everything down so that I can properly take care of a BP, but there was some mixed information and some things that I just couldn't find any info about!

I'm going to either be buying a sub-adult Normal or a baby morph (I'm trying to choose between a Cinnamon, Mojave, Genetic Stripe, or Pastel), and I'm planning on housing in a 36"x18"x16" glass terrarium with three sides covered for more security. I'm getting it set up with a ZooMed Reptitherm UTH designed for 30-40 gallons with a thermostat.

I'm setting everything up at least two weeks before I actually get the ball python, that way I can make sure that I've got a handle on keeping the temperatures and humidity stable BEFORE it can affect my snake!

Now here's where the questions start!:

-I live in Southern California and I often keep my window open, so my room temperature tends to vary between 73 and 78 degrees. Because of that, I was planning on getting a heat lamp and connecting it to a dimmer so I can keep the terrarium ambient temperatures high enough. I was going to get a UV night light (Specifically the ZooMed Nighttime Moonlight bulb) so that I could keep it running whenever needed and it wouldn't stress out my snake. My question is, is that appropriate? Or should I get something else? I haven't been able to find much information on what kind of wattage to use for what size tank, so what wattage would I want to get for a 40-gallon?

-I've seen a lot of people on here specifically say that they don't use in-tank thermometers but instead rely only on a temperature gun. I know that temp guns can get more accurate readings wherever you want, but is this really an okay setup? Or do you think it's something that should only be used in supplement to thermometers?

-IF using a probe thermometer, is hot glue a safe way to secure it at the bottom of the terrarium, so long as care is taken to make sure there are no sharp edges (I'm avoiding tape for obvious reasons)? I'm worried about the snake potentially moving the probe out of place.

-I've been looking at weight scales and I've heard a lot about people having them; is this a tool that you feel is necessary, or just something that's nice to have?

-There seems to be a lot of debate about what kinds of substrate to use. I personally use aspen shavings for my KSB but that's because they like it dry and they like to burrow a lot, but I heard that aspen isn't very good at holding humidity. From what I can gather, it looks like the top choices seem to be cypress, coconut husk, and I also heard good things about EcoEarth. Which do you recommend?

I feel like I wanna emphasize with the weight scale and temp gun questions that I'm definitely not looking to cut corners on costs, I just want to see what people's opinions are on the topic! Sorry for such a long post and sorry for all the questions, and thank you so much in advance!