The shafts are
stainless steel, you can prove this because stainless steel cannot be
picked up with a magnet. Stainless steel will develop a surface
oxidation, it is not really rust because it will never procede beyond
the surface. You will see the same thing on stainless steel forks
and knives when taken from the dishwasher, if you look close they
have small spots of oxidation. You can scratch it off with your
fingernail or even a cloth. The shafts should not come out. All
stainless steel shafts in pumps show this, if you remove the end
pieces from a maxi jet shaft you will see the same thing. The
problem is that the shafts have come out but any pump I send you will
form small spots of surface oxidation and this will not harm the
reef, if it did they would not sell iron as a reef supplement