My buddy and I always sit around talking catfish tactics. We talk about it so much that my wife says we sound like a bunch of fishing geeks:roll_eyes:...I guess that would be a good thing:smile2:...anyways, here's something that came up in a conversation with my son (Donte) and my fishing buddy (Chris) that I never really gave though to...my finder's transducer gives water temp...but I never questioned wether that temp is water surface or the entire depth being read? I have a humminbird pirahna...nothing fancy...can anyone shed some light on this subject for me? If it only reads water surface, do you have rule of thumb that you go by to guesstimate bottom temps? thanks.