Two weeks ago I went to turn on the lights on my row of tanks and when I reached over the top of one it felt way to warm. I looked in the tank and the fish were dead, but I could see the silver molly still swimming. I grabbed my instant thermometer and when it got to 102 I grabbed the net, caught the molly, dumped it into the next tank. Then I stood there saying to myself “Stupid, you just probably shocked it to death.” (That tank was 77) Reason reigned and I decided I couldn’t risk another shock by putting it back in the hot water, so I left it. ( Its two weeks and it survived.) I lost 3 platies and a betta, but in the process of removing them I found that a little ½” fry had also survived which I left in the tank and shut off the heater like I should have done in the first place. It was an old heater - very old - looked like one my kids had 40 years ago and I had some warnings that it was hard to adjust, but hadn’t decided what to replace it with. I have now bought an Aqueon Pro by mail and I have never seen a heater like it - no glass! Its suppose to be indestructible. (Seem like something Kerry would like with his water dogs) Its just a clean black plastic tube with a tiny light that is either red or green. With a dark back ground it is hardly noticeable. I can’t yet say anything about its performance but it is suppose to be accurate within a degree. (Its adjustable) 
