Went to feed fishies this evening and the temp of the water was nearly 95 - so I quickly emptied about a third of the tank out and added cold treated water and got the temp down to about 85. I took out the heater and now I'm testing it to see what happened. Even if it works properly again, I won't take a chance by reusing it., just keep it as a spare. Can anyone suggest a heater for a 180 litre juwel tank? I lost one of my neons during this but I hope I caught it in time and won't lose any more. I feel awful puting them through this -