MP40 loss of magnetic pull?

MTsquared · Sep 7, 2021

One of my MP40 dry side came crashing down off of my tank in the middle of the night. Heard the loud noise and went to check to see what had fallen over. Didn’t notice anything around the house that would’ve caused the noise so went back to bed. When I woke up in the morning and was looking at the tank I saw the propeller side sitting in the sand bed and the dry side was on the wood floor. That’s when I figured out that is what caused the loud noise I heard. The dry side sounded like it was still doing it’s thing. I tried to put it back together on the tank however the magnetic field between the two seemed to be somehow messed up as they will not hold together. I am not currently able to use that MP40 and it is currently unplugged. Any tips/ ideas/ suggestions would be helpful as I’m not really sure what to do to try to fix the situation. Also I now only have one MP40 for flow in addition to the main return.

Ultra Aquatics · Sep 7, 2021

Make sure you are using the correct spacer. Mine did the same thing until I realized I was supposed to be using the thinnest spacer for my 280g.

homer1475 · Sep 7, 2021

They will not "couple" with the dry side running. Also the dry side should be supported with the supplied "stickie" hanger or they will continue to fall off.

alton · Sep 7, 2021

As Homer said use stickie and tie wrap plus add a second. Because one day the first stickie will fail.

homer1475 · Sep 7, 2021

alton said:
As Homer said use stickie and tie wrap plus add a second. Because one day the first stickie will fail.

So true! I've even super glued them to my tanks glass, and they still fail at times.

MTsquared · Sep 7, 2021

homer1475 said:
They will not "couple" with the dry side running. Also the dry side should be supported with the supplied "stickie" hanger or they will continue to fall off.

Ok thanks that makes sense. I tried to put it back on while it was still running. Will give it a go the other way and see if that works. Yes I have the stickies just need to put them to use and this seems like a good reason to do that.

WVNed · Sep 7, 2021

I learned that lesson when one fell on the floor and broke. It is not cheap to fix.
The wet side will fly off if it is stalled by a snail crawling in of something getting caught between the propeller and cage.

MTsquared · Sep 20, 2021

So it seems like the dry side on both MP40 are now randomly losing their magnetic pull. Any reason as to why this would be happening or suggestions on how to fix? Don’t want to keep having this issue as the wet side will drop off in the tank when the dry side loses its magnetic pull. The wet side narrowly missed a decent size acro colony this time thankfully.