Also!!
Get an Accurite thermometer from walmart. Make sure to get the one with the probe. It should be like 12 bucks or something close to that. Without doing so will result in inaccurate temps. I had to set my tstat a lot higher to achieve the right temp. I just hot glue (thanks to dr.del) the probe inside the tub, right over the heat tape. Therefore when your adjusting the tstat you will know EXACTLY what temperature your at without assuming. So tstat probe is on the outside, thermometer probe on the inside. Good luck!