/headscratch.. so this silver mold prevention pellets thing. Could you just throw silver ingots or jewelry in there ? does that work the same.
the same, no but it will have some effect, as will copper, both are "contact poisons", basically if a microorganism touches either it dies, or at least it is how i understand it from what i have ready about 5 years ago, the pellets will have much higher surface area so be much more efficient and silver will not make green deposits everywhere
oh and both can be irritants, copper much worse than silver though, and you need to be in direct contact with either for an awfully long time for them to start to attack your skin.
you also technically use hard bar soap, should have a similar effect, if my biology and chemical understanding is not too wrong.