Finding a needle in a hay stack (actually a rock pile)

[tzylak]

Help! I dropped a sewing needle into my DT rock pile!!
I tried to retrieve it with a magnet but have a hunch that it slipped way down to the bottom of the stack.
Allegedly, the metal is high-carbon steel with some trace of nickel, platinum or titanium. I am saying that with hopes of not having to tear down my aquascape in order to retrieve the stupid thing.
Now I am open to your suggestions on the matter.
Should I bother digging for it??

 

[Reef Frog]

Considering the tiny volume of metal and the high quality steel alloy, my gut tells me that it won't degrade in such a way as to contaminate your tank and kill or make your animals sick. But that's just an educated guess based in limited knowledge of metals.

I'm the kind of person that would get it out "just because" however. Did you check a similar needle to make sure it is magnetic? Some steel based metals are demagnetitized. If it is magnetic I'd keep trying with a powerful magnet in the general area, trying different approach angles in case it is wedged in tight. I hope you don't have to do a tear down.

Just curious, what were you doing with a sewing needle?

 

[ca1ore]

I've dropped a few single edge razor blades into my rocks over the years and never bothered to retrieve that. Usually find them when breaking down a tank in various stages of rusting. Never seem to do any harm; think of them as incidental GFO.

 

[Sk8r]

Steel per se, or iron, is not a big problem such as copper is. The principle reason not to use it is that it quickly rusts and ruins the tool. It won't hurt your tank in that tiny volume. If that were a penny, or brass screw, I'd be telling you to move whatever have to and find it.

 

[cincyjim]

I'd have to remove because it would drive me nuts knowing it was in there. Also, Murphy's Law would dictate that I would forget it is there and stick myself with it at some point.

 

[tzylak]

Why, oh why?. . . I took my turkey baster, pierced the needle in question thru its output nozzle, skewered a piece of shrimp on it to spot feed my Serpentine Sea Star.
It was interesting how the creature knew which way to apply the liberating force to pull it off. On the third feeding the needle slipped out. . .
Yes, I checked out needles out of the same set and they are somewhat magnetic.
You clued me in to take another needle, immerse it in my sump (for a while) to see the rate of rust. - As a control specimen

 

[Sk8r]

Stainless can take months to rust. Plain steel faster, and iron pretty fast. I keep a stainless blade in my TUnze Care magnet that's generally submerged, and it's not rusted yet, in about 3 months.