I bought my temp gun at an auto parts store and its actually pretty awesome. You can continuously scan around a tub or other enclosure and it records and displays the highest temp while displaying the current temp of what you are scanning... if that makes sense? I think it was about $15 dollars at Autozone and I bought it for something else but ended up using it exclusively for my bps. Just keep in mind that it only tells you temps of a surface which is helpful for checking hot spot temps. I don't think you can get an accurate temp of water with a surface temp gun. Look at auto parts stores or at target or walmart in their auto parts departments for one. Hope that helps.