Aquaman vs. The Atom...?

I guess. I don't think the plankton trick would work because he can just shrink himself SMALLER than the plankton.

I AM unsure of how Atom would react too the pressures of the deep though.

I don't think it matters how deep the Atom is underwater if he is the size of a water molecule.

I just had a thought. How does the Atom breathe when he is the size of an air molecule?

I've always wondered that myself. Has it been said in the comics at all?

He breathes this infinitesmal smaller "air" molecules. Apparently there may be no limit to smaller things.