Power head Mystery?

[dan2x38]

I have a Koralia 3 in my 75g. I added a 4th PH so now have 2 Evolution 1400s, 1 Evolution 1040 and the K3. I removed the K3 for a bit to replace it and added the new 1400. The K3 sat around for approx. 1 week. The magnet on the outside fell behind the tank when I pulled out the K3. I decided it was time to add the K3 back so dug out the magnet from behind the the stand. Dusted it off but the strangest thing the magnet had reversed polarity? Totally serious if I put the magnet towards the PH it pushed aside by the polarity of the PH base magnet. 

I had to take the outside magnet apart and turn the magnet inside over then reseal it. Put the K3 in the tank placed the outside magnet against the glass and it worked perfectly!

Has this ever happened to anyone else? How the hell did it happen in the first place? Very strange for sure it baffled me? Not always hard to do... LOL

[HomerJ]

Any chance you have a DC power cord back that that is coiled or looped?  I remember magnetizing things like nails by wrapping them with a wire and hooking them up to a DC source.

[dan2x38]

I thought about that - but the answer is no. By the way still holding the fix worked just totally bizarre.

[Hookup]

Impacts to magnets can cause this. You can reverse the process.  I'm a going to google it and see what I can find.  This was grade school "magic science".  I believe you'll need an iron rod and a hammer.  But were going back over 20 years and the memories not clear n