Ice forming on fridge "fins"

I am real old, and just "learnt" the importance of frig temps based upon my recent experience with both our house and RV units. But after monitoring both, I now will never be without a way to know the temps. I used a wired remote unit. Our house was running well into the 40s, and that is just too warm -- recommendations are 35 or so. Now, I have adjusted it to almost exactly 35 degrees. I can imagine with a house full of youngins that the temp would probably be real close to 50 or more most of the day, but they eat a lot, so maybe it isn't that bad.

Thanks for the recommendations on the remote units -- will get two for both house and RV.