Basically I’m worried about my cobalt Neo-therm 75watt heater failing. I’ve been using it in my 20 gallon tank for about a year now after a cheap 100watt heater failed on me. The winter here has been super cold, the house is kept at a minimum of 68°. I would normally keep the tank at 78° but noticed the thermometer was only reading 76° So maybe a week ago so I bumped the heater up to 80° and moved it over closer to the intake of the filter right above where there’s a bubble bar in the back to improve circulation. Yesterday I noticed the heater blink 78° and then followed by blinking 82° before settling on 80° again. Today after sitting down to feed the fish after work I noticed it blink either 96° or 94° maybe once or twice. It kind of made me jump out of my chair in shock, ready to stick my hand in the water to make sure my fish werent boiling until I remembered about the thermometer in the corner, which is reading 81°. So my question is are the signs that my heater is failing? I did buy a cobalt neo-therm 100watt heater when it first wasn’t keeping up the temps. I could put the 100watt heater in the 20 gallon tank and move the 75watt heater to one of my 10 gallons, and than move the 50watt also cobalt neo-therm to a 5.5gal so none of them would be working as hard... would that be too much wattage for any of those tanks? Or am I worrying over nothing ?