
My 800W Hygger HG921 broke down after 6 months. The wrench light was on and the temperature on the display was over 97 degrees. I put my finger in the water to check the temperature and felt a small electric current. I turned off this heater and the electric current disappeared. I'm glad my Oscars didn't get electrocuted. Hopefully the second/spare hygger in my tank will last longer. Update: A crack was found in the PCB insulation in the heater housing.

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