i.e. anything that can fit in his mouth or smaller (unless it is edible). On two separate occasions, Tiny swallowed the following:
Black cylindrical filter sponge (4 inch one) and 'gave it back' about 1 week later. Only problem was how long it was going to take to relieve itself.
This second one was more of a concern. He 'ripped' off the plastic bottom of an ELITE 100 (About 2X1X2.5 inch) filter; barely was able to keep it in his gaping jaw and then finally 'swallowed' it. Had it in his belly for almost three weeks (could see the outline, never moved) before it appeared in the tank again (unchanged).
During this time I maintained him on a diet of pellets and frozen cubes in order for him to keep up his strength.
I was considering a 'procedure' with clove oil and some long needlenose pliers; Thankfully I waited (patience is a virtue?) long enough for nature to take it's course. And while I cannot attest to this by witnessing the extrication myself, I believe that in both instances the objects came out the same way they went in.