Magnets safe to submerse?

[pecan2phat]

Does anyone know if the outside magnet for a 6040 is safe to immerse in saltwater? Wanted to place the pump on the false wall of an AIO tank.
In the past, I've placed the old H type magnets from a 6000 inside an overflow and 1 out of two would eventually swell up indicating that they are not entirely epoxy sealed.

TIA

 

[rvitko]

Even with the old H magnets both halves are waterproof, if they swell up either they had a defect or had been dropped/over heated and developed cracks.

 

[pecan2phat]

Thanks Roger, I'll go ahead with confidence now.