hey there, sorry in the poll, mistook the stickon with the digital thermo with probe in the tank. I found those to be accurate, second in line would be the floating one. the stainless steel one I dont have exp with and would not want the steel seen in the tank.
the stick on ones are hichly in-accurate...dont like putting metal into a tank unless absolutle neccesary...Floating or electronic all the way for me....
A digital thermometer that sticks on the inside of the tank is what I use, together with a sticky on one; I don't fully trust the sticky on one.
I like the internal digital because I can move it around in the tank and get a good reading for the temp; the floater is only going to give you the surface temp.