
I read the bad reviews and thought yes. I bought 2 of these last week. They were both set at 83 degrees. They heated the water around them so that it literally boiled on the glass of the heater. Then both of them cracked leaving glass on the bottom of both of my aquariums. I pulled a fish out of one of those burnt tanks yesterday and couldn't figure out what the problem was; Since all the water was ok, the exact feeling is a little warm. Now I know

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