I completely understand your worrying...I am totally neurotic when it comes to my snakes...so I get it. As far as the UV light goes, there is research that has found benefits in the use of UVB light in garters. Some people believe they need it, other don't. I have a UVB flourescent strip light for my easterns...I try to put it on for a couple hours a day. They don't seem to like the bright light all that much...but I try to put it on for a little while so that they can get the benefits from it...if there are any to be had. As far as heat goes, I think it depends on the species, and on the particular snake and what that snake prefers...but most people recommend a warm side in the low to mid 80's and a cool side in the low to mid 70's...with a drop in night temps. Some people recommend heat at night, and others do not. I keep my warm side around 82-84 and my cool side around 75 during the day for my eastern garters. I do use heat at night in the winter...letting it drop to around 78 on the warm side and to around 70 on the cool side at night. For my albino checkered...I keep it between 82 and 86 on the warm side and around 75 on the cool side during the day and at night...he likes his temps warmer. Keep in mind that garters can handle and need a night temp drop...as long as the temp doesn't go below about 66...she should be fine at night. Some members don't use any heat at night...as long as your house doesn't get too cold...it's not always needed.