This is just an observation and totally unrelated to your issue.
When I first saw the picture in your opening post I had to double take. The positioning of your tank in relation to the opening of the door is scary. If a child or an excited dog came rushing through that door, or a draught caught it, the door handle could smash into your tank, which may be catastrophic.
If I was you I would add a doorstop on the floor to totally eliminate the potential for disaster.