Does anyone recommend a specific water temperature guage? I've seen several types online but not much to choose from in any of the stores I've been in. I'm thinking something digital so I don't need my glasses to read it, vs. reading a mercury scale. It s@#s to get old! I checked the fishing stores like Gander Mtn. but they didn't have much. I was also thinking about going to the pool supply store to see what they have. Just wondering what everyone else is using?